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Posted

My first Porsche was a 1999 C2 cabrio, 300 hp, bought in 2010 with 64K miles for $24.5K. It was just the base model, came with a lovely matching hard-top. And though 11 years old it was immaculate, inside and out, full dealer service history. In fact smelt and sounded 'newer' than most new cars. For 3 yrs it was my 90 miles/day commuter car: the thought of driving it helped get me out of bed at 545am, really!

Then at 115K I had a mishap avoiding a deer, and wrote the car off. I topped up the insurance payment ($21.5K, thank you State Farm!) and got a 2007 997.1 C2S 6-speed manual cabrio, 11.5K miles, with the Sports pack (so 355 hp).

I loved it at first, thought it was an incremental improvement over the 996, but now, 4,500 miles later I'm not so sure.

What's obviously better?

Interior. I thought the full leather interior of my 996 was pretty darn good, but the stitching on the 997 is like a Prada handbag - it's Rolls Royce vs Jeep. The headlights are the same story - good just got better! Ditto the ragtop, seats (heated, with the top down at 0C/32F - wonderful!). Engine sounds on start up (throaty burble, with some water on the lungs; transforms to the growling purr of a cat chasing a bird; then onto a sinfonic roar). I like the tire pressure monitoring system, still not sure if I fully trust it though. Truly amazing is the cabin comfortableness with the top down. When it's freezing, a thick jacket is all I need if the seat heater is on and the cabin temp is set suitably high - say 80F/27C. That much of the improvement comes from the mesh screen device (which was missing from my 996) was proved by not using it one morning - i was deeply cold after the 1hr drive to work.

Exterior. Well, the return to round headlights makes purist sense - though I prefer the more slippery 996 profile and front end. And it looks wonderful, big fat tires, flawless deep blue paint, better profile with hood up (and a better hood) - I always pause to admire it for a second or two before climbing in.

What's not to like?

Well - and I'm sure I'll be accused of either incompetence or heresy or both for this: the 6 speed transmission is ****e! After having the dealer install the short shift kit, it was subjectively maybe a little better. But N to 1st often needs a throttle blip to allow the teeth to engage at all. I find I'm only doing seamless 1st to 2nds about 50% of the time. 2-3, 3-4, 4-3 are great, the downshifts being gratifyingly better with double declutching (sounds like dopplekoppling, eh Heinz?). But 3-2 can be hit or miss. 5 and 6 are fine, but pretty redundant for city driving. I think it better as a 4+2 than a 6, if that makes sense. But in all honesty, every other manual I've driven (which I did exclusively for my first 22 driving years) was easier to shift, up or down. (The clutch, BTW, is fine).

The only other negatives are i) PCM/phone system (which I'll replace) - just totally lame. ii) I miss the volts on the gauges. I'm confused by oil vs water temp: the dealer says it's good to go if the water is at 175, even if the oil temp hasn't changed. That just doesn't seem right to my simple mind! iii) I want a dipstick, was very surprised to learn it was abandoned for the 997 onwards.

My final impression is that the 997.1 is yet another incremental engineering triumph over it's predecessor. The performance, reliability, fit and finish, luxuriousness are so obviously much better, it's a wonderful drive but....it's bigger, feels heavier. The 996 is noticeably smaller and though 11 lbs/hp vs 10 lbs/hp, it seemed just...tighter. I liked keeping both hands on the wheel, loved the Tiptronic both in rush hour and in the hills.

So, after 3 months I'm seriously wondering whether I'm the right person for this car...

Posted (edited)

You may not be. Now, I owned a 1999 C2 for two years so I feel qualified to have this discussion.

The transmissions are not as good. There is more drive lash and shifting in and out of 1st and second gears can be notchy, sticky or whatever especially when cold. But, I would NEVER drive a Tiptronic. I'm a manual guy. I have learned to deal with it. Use Miller's EE 75W 90 Nanodrive transmission oil and things will improve a bit.

I have been a 911 guy since....1968. If you think those other headlights look better you need another drink. Round headlights are it. NOTHING ELSE will do on a 911 and that is why 966 cars are worth less and Porsche, with it's tail between it's legs went right back to round lights.

You need new tires. If you think a 996 car handles near as well you either can't drive or you have bad tires. Get Michelin Super Sports have them expertly balanced and ROCK AND ROLL. I have my car in and out of 4 wheel drifts all the time. It is SO easy in the 997 S.

Ditch the PCM. Get an Alpine or Kenwood Nav, a NAV TV most head unit replacement module, a mount kit for the 997 and you will have what looks like a factory system with the best NAV, Bluetooth, iPod integration and better sound. That version of PCM is Becker trash. (I think Becker?) Talking about learning as you go.

The gauges are wonderful. Your dealer is full of crap. You are good to go when your oil temp is over 200. The pistons, heads and upper block may be warm when the water temp gets to 175 but the rest of the engine (crank bearings) is not. Just don't horse it until the oil temp is up. Which means drive like your grandmother. (Actually, my grandmother was hell on wheels)

Edited by Mijostyn
Posted

You may not be. Now, I owned a 1999 C2 for two years so I feel qualified to have this discussion.

The transmissions are not as good. There is more drive lash and shifting in and out of 1st and second gears can be notchy, sticky or whatever especially when cold. But, I would NEVER drive a Tiptronic. I'm a manual guy. I have learned to deal with it. Use Miller's EE 75W 90 Nanodrive transmission oil and things will improve a bit.

It's horses for courses, I guess - but if you have NEVER driven one, not sure how you can judge...

I have been a 911 guy since....1968. If you think those other headlights look better you need another drink. Round headlights are it. NOTHING ELSE will do on a 911 and that is why 966 cars are worth less and Porsche, with it's tail between it's legs went right back to round lights.

I actually agree the rounds look more sympathetic, but if the 996 and 997 were to same scale and windscreen slope, I'd put momey on the 996 having a lower CD (yes I know the actual numbers the 996 is 0.30 and the 997 is 0.29).

You need new tires. If you think a 996 car handles near as well you either can't drive or you have bad tires. Get Michelin Super Sports have them expertly balanced and ROCK AND ROLL. I have my car in and out of 4 well drifts all the time. It is SO easy in the 997 S.

It came with brand new Bridgestones, but your point is well taken. Will get the Super Sports at the next replacement. I can't be bothered to deal with the '...either you can't drive or....' other than another option might indeed be a crap transmission (design or my particular unit).

Ditch the PCM. Get an Alpine or Kenwood Nav, a NAV TV most head unit replacement module, a mount kit for the 997 and you will have what looks like a factory system with the best NAV, Bluetooth, iPod integration and better sound. That version of PCM is Becker

trash. (I think Becker?) Talking about learning as you go.

Agreed

The gauges are wonderful. Your dealer is full of crap. You are good to go when your oil temp is over 200. The pistons, heads and upper block may be warm when the water temp gets to 175 but the rest of the engine (crank bearings) is not. Just don't horse it until the oil temp is up. Which means drive like your grandmother. (Actually, my grandmother was hell on wheels)

My dealer service manager is a veteran P guy (Gunther at Porsche of Fremont) I trust implicitly, so I doubt he's full of crap. But I have ignored his blessing and keep the revs below 4K till the oil is hot. But if oil temp is what really matters, ditch the water temp gauge and bring back volts. Having oil temp and pressure close would also be better ergonomics...

Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Posted

I'm a 996 man and I have to say in view of the tendancies of the electronic oil gauge to give odd reading, I don't think I would buy a car that does not have an oil dipstick.

Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

post-72654-0-29800100-1389536704_thumb.j

  • Moderators
Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

+1 I have to agree with Silver_TT on this one. While some have gotten away with using aftermarket gear oils in these gearboxes, most have not. Problems have ranged from pronounced noise, to poor shifting, and actual mechanical failure problems. Considering the cost of either rebuilding or replacing these gear boxes, and the simple fact that the OEM lube is a full synthetic made to Porsche specs and not an API "GL" catagory, it seems counter intuitive to start playing around. The OEM product is readily availiable, not all that expensive, and works very well.

Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

+1 I have to agree with Silver_TT on this one. While some have gotten away with using aftermarket gear oils in these gearboxes, most have not. Problems have ranged from pronounced noise, to poor shifting, and actual mechanical failure problems. Considering the cost of either rebuilding or replacing these gear boxes, and the simple fact that the OEM lube is a full synthetic made to Porsche specs and not an API "GL" catagory, it seems counter intuitive to start playing around. The OEM product is readily availiable, not all that expensive, and works very well.

Take a deep breath. OK.

What makes these transmissions special is they are transaxles. The transmission and the hypoid final drive are in the same case. The transmission itself is the rather standard constant mesh synchronized transmission which Porsche was the very first to introduce in the 1952 356!! I'm sure JFP knows the deal well. For those of you who do not check this out http://www.youtube.com/watch?v=vOo3TLgL0kM . The problem with the transaxle designs is that hypoid final drives generate a lot of friction and require heavier lubes. Syncromesh transmissions do not like their oil to thick or the baulk rings do not clutch correctly, they float. Revs don't match up and you can't get the car in gear. So, what Porsche did was spec a gear lube that is at the very thinnest of the SAE 75W90 range with a very high Viscosity index. The higher the viscosity index the less the oil's weight changes with temperature. The oils had to have a cSt less than 600 at 0 C. The first to meet that spec was Shell with what was then called Shell Transaxle. It is now called Spirax S5 ATE which you can get in 20 liter drums. Ferrari uses it in their transaxle cars. Porsche use to use it but then Mobil made a marketing deal with Porsche. Thus Mobilube PTX (Porsche TransaXle) was born. These two are the only 75W 90 gear oils that meet Porsche's entire spec. The problem with them is that they are very thin when warm. Why a problem you ask??

All of these transaxles have a degree of drive train lash. Individual cars better or worse depending on luck and the weather. My car is a bit worse in this department. Don't believe me?? Next time you have your car up, put it in gear with the e-brake off. Grab a rear wheel and rotate it back and forth. You will have between 5 and 10 degrees of free play. That is the lash. You can feel it when you drive. Rapid large transitions on an off the gas produce a "thunk" which you feel in seat of your pants. Drive with the window down. You will also notice a lot of transmission noise as say compared with an Audi manual. This stuff is what got me started.

Science and specs tell us what to do. An SAE 90 oil can have a viscosity of any where between 13.8 and 18.8 cSt at 100 C. PTX is 14.5 cSt with a viscosity index of 194 (perfect is 200) Spirax is pretty much the same. All the other oils except Millers are around 15.5 cSt at 100 C with a viscosity index ranging from terrible like Delvac at 140 up to Redline at 176. Millers is special because their EE Nano oil has a viscosity of 17.8 at 100 C with a viscosity index of 183.

These oils perform exactly as you would expect. With the exception of Millers none of the oils do much to soften the lash and quiet the transmission. Delvac is just plain stupid below 10 C. If you try to jam the car into gear you might score the dog teeth on your syncro rings.

Until the transmission reaches full temp, which can take a while, shifting with Delvac ranges from poor to worse. The other oils are OK if you live and drive in environments that are always over 15 C. But if you live and drive anywhere where the Temp drops below 0 C Stick to the PTX or Spirax with ONE exception.

Millers is an interesting British company that has been around for a while making lubricants for industrial machines. In the last decade they started getting into motorsports and recently started formulating synthetic oils with nano particles. These particles have been absolutely proven to lower friction by up to 25%. All the science is available on-line. The stuff is very expensive. The gear oil got me to try the motor oil which I now use.

Anyway, The Millers most definitely quiets the transmission enough so that even my wife notices it. It takes about 50% of the sting out of the lash. It most definitely shifts better when warm than PTX. At 10 C shifting into 1st and second get a bit stiff but then something strange happens. The other oils including PTX get stiffer as they get colder. Millers starts to get stiff at 10 C but then gets no stiffer all the way down to -8 F. Which is as cold as the car has gone so far. I have used Millers EE exclusively for almost 10,000 miles and everything is just peachy keen. The only things special about PTX other than its viscosity is that it is overloaded with very expensive viscosity modifiers which dilute the oil's friction reducing capability and Mobil has a marketing deal with Porsche. If you don't like marketing deals and you are paranoid about using other oils by all means go with the Spirax.

Posted

Did you not look at the picture I uploaded? Look at the teeth.

I'm not sure where you get your "science and specs". I have spoken at length about this topic with Stan, the owner of Gbox. I'm sorry, but there's frankly no way I'm going to be able to take your advice with your tests over his 30+ years of knowledge from working on Porsche gearboxes. Ask around, people in the know respect his knowledge. I had a conversation with him about this specific topic and he told me that if you use non-OEM gear oils you are playing with fire. Might take a few thousand miles, might take tens of thousands of miles....but over time you're running a higher risk. You never really know what shape your gearbox is in until they get inside it. It really is incredible, these gearboxes are extremely complex.

I just like for other people out there to know the truth: Frankly that if you use any other oil aside from OEM fluid, you're rolling the dice and taking a big chance for very little upside. Sometimes what's cheap is expensive.

  • Moderators
Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

+1 I have to agree with Silver_TT on this one. While some have gotten away with using aftermarket gear oils in these gearboxes, most have not. Problems have ranged from pronounced noise, to poor shifting, and actual mechanical failure problems. Considering the cost of either rebuilding or replacing these gear boxes, and the simple fact that the OEM lube is a full synthetic made to Porsche specs and not an API "GL" catagory, it seems counter intuitive to start playing around. The OEM product is readily availiable, not all that expensive, and works very well.

Take a deep breath. OK.

What makes these transmissions special is they are transaxles. The transmission and the hypoid final drive are in the same case. The transmission itself is the rather standard constant mesh synchronized transmission which Porsche was the very first to introduce in the 1952 356!! I'm sure JFP knows the deal well. For those of you who do not check this out http://www.youtube.com/watch?v=vOo3TLgL0kM . The problem with the transaxle designs is that hypoid final drives generate a lot of friction and require heavier lubes. Syncromesh transmissions do not like their oil to thick or the baulk rings do not clutch correctly, they float. Revs don't match up and you can't get the car in gear. So, what Porsche did was spec a gear lube that is at the very thinnest of the SAE 75W90 range with a very high Viscosity index. The higher the viscosity index the less the oil's weight changes with temperature. The oils had to have a cSt less than 600 at 0 C. The first to meet that spec was Shell with what was then called Shell Transaxle. It is now called Spirax S5 ATE which you can get in 20 liter drums. Ferrari uses it in their transaxle cars. Porsche use to use it but then Mobil made a marketing deal with Porsche. Thus Mobilube PTX (Porsche TransaXle) was born. These two are the only 75W 90 gear oils that meet Porsche's entire spec. The problem with them is that they are very thin when warm. Why a problem you ask??

All of these transaxles have a degree of drive train lash. Individual cars better or worse depending on luck and the weather. My car is a bit worse in this department. Don't believe me?? Next time you have your car up, put it in gear with the e-brake off. Grab a rear wheel and rotate it back and forth. You will have between 5 and 10 degrees of free play. That is the lash. You can feel it when you drive. Rapid large transitions on an off the gas produce a "thunk" which you feel in seat of your pants. Drive with the window down. You will also notice a lot of transmission noise as say compared with an Audi manual. This stuff is what got me started.

Science and specs tell us what to do. An SAE 90 oil can have a viscosity of any where between 13.8 and 18.8 cSt at 100 C. PTX is 14.5 cSt with a viscosity index of 194 (perfect is 200) Spirax is pretty much the same. All the other oils except Millers are around 15.5 cSt at 100 C with a viscosity index ranging from terrible like Delvac at 140 up to Redline at 176. Millers is special because their EE Nano oil has a viscosity of 17.8 at 100 C with a viscosity index of 183.

These oils perform exactly as you would expect. With the exception of Millers none of the oils do much to soften the lash and quiet the transmission. Delvac is just plain stupid below 10 C. If you try to jam the car into gear you might score the dog teeth on your syncro rings.

Until the transmission reaches full temp, which can take a while, shifting with Delvac ranges from poor to worse. The other oils are OK if you live and drive in environments that are always over 15 C. But if you live and drive anywhere where the Temp drops below 0 C Stick to the PTX or Spirax with ONE exception.

Millers is an interesting British company that has been around for a while making lubricants for industrial machines. In the last decade they started getting into motorsports and recently started formulating synthetic oils with nano particles. These particles have been absolutely proven to lower friction by up to 25%. All the science is available on-line. The stuff is very expensive. The gear oil got me to try the motor oil which I now use.

Anyway, The Millers most definitely quiets the transmission enough so that even my wife notices it. It takes about 50% of the sting out of the lash. It most definitely shifts better when warm than PTX. At 10 C shifting into 1st and second get a bit stiff but then something strange happens. The other oils including PTX get stiffer as they get colder. Millers starts to get stiff at 10 C but then gets no stiffer all the way down to -8 F. Which is as cold as the car has gone so far. I have used Millers EE exclusively for almost 10,000 miles and everything is just peachy keen. The only things special about PTX other than its viscosity is that it is overloaded with very expensive viscosity modifiers which dilute the oil's friction reducing capability and Mobil has a marketing deal with Porsche. If you don't like marketing deals and you are paranoid about using other oils by all means go with the Spirax.

Glad you like it, but we have had customer's that had zero luck with it.

Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

+1 I have to agree with Silver_TT on this one. While some have gotten away with using aftermarket gear oils in these gearboxes, most have not. Problems have ranged from pronounced noise, to poor shifting, and actual mechanical failure problems. Considering the cost of either rebuilding or replacing these gear boxes, and the simple fact that the OEM lube is a full synthetic made to Porsche specs and not an API "GL" catagory, it seems counter intuitive to start playing around. The OEM product is readily availiable, not all that expensive, and works very well.

Take a deep breath. OK.

What makes these transmissions special is they are transaxles. The transmission and the hypoid final drive are in the same case. The transmission itself is the rather standard constant mesh synchronized transmission which Porsche was the very first to introduce in the 1952 356!! I'm sure JFP knows the deal well. For those of you who do not check this out http://www.youtube.com/watch?v=vOo3TLgL0kM . The problem with the transaxle designs is that hypoid final drives generate a lot of friction and require heavier lubes. Syncromesh transmissions do not like their oil to thick or the baulk rings do not clutch correctly, they float. Revs don't match up and you can't get the car in gear. So, what Porsche did was spec a gear lube that is at the very thinnest of the SAE 75W90 range with a very high Viscosity index. The higher the viscosity index the less the oil's weight changes with temperature. The oils had to have a cSt less than 600 at 0 C. The first to meet that spec was Shell with what was then called Shell Transaxle. It is now called Spirax S5 ATE which you can get in 20 liter drums. Ferrari uses it in their transaxle cars. Porsche use to use it but then Mobil made a marketing deal with Porsche. Thus Mobilube PTX (Porsche TransaXle) was born. These two are the only 75W 90 gear oils that meet Porsche's entire spec. The problem with them is that they are very thin when warm. Why a problem you ask??

All of these transaxles have a degree of drive train lash. Individual cars better or worse depending on luck and the weather. My car is a bit worse in this department. Don't believe me?? Next time you have your car up, put it in gear with the e-brake off. Grab a rear wheel and rotate it back and forth. You will have between 5 and 10 degrees of free play. That is the lash. You can feel it when you drive. Rapid large transitions on an off the gas produce a "thunk" which you feel in seat of your pants. Drive with the window down. You will also notice a lot of transmission noise as say compared with an Audi manual. This stuff is what got me started.

Science and specs tell us what to do. An SAE 90 oil can have a viscosity of any where between 13.8 and 18.8 cSt at 100 C. PTX is 14.5 cSt with a viscosity index of 194 (perfect is 200) Spirax is pretty much the same. All the other oils except Millers are around 15.5 cSt at 100 C with a viscosity index ranging from terrible like Delvac at 140 up to Redline at 176. Millers is special because their EE Nano oil has a viscosity of 17.8 at 100 C with a viscosity index of 183.

These oils perform exactly as you would expect. With the exception of Millers none of the oils do much to soften the lash and quiet the transmission. Delvac is just plain stupid below 10 C. If you try to jam the car into gear you might score the dog teeth on your syncro rings.

Until the transmission reaches full temp, which can take a while, shifting with Delvac ranges from poor to worse. The other oils are OK if you live and drive in environments that are always over 15 C. But if you live and drive anywhere where the Temp drops below 0 C Stick to the PTX or Spirax with ONE exception.

Millers is an interesting British company that has been around for a while making lubricants for industrial machines. In the last decade they started getting into motorsports and recently started formulating synthetic oils with nano particles. These particles have been absolutely proven to lower friction by up to 25%. All the science is available on-line. The stuff is very expensive. The gear oil got me to try the motor oil which I now use.

Anyway, The Millers most definitely quiets the transmission enough so that even my wife notices it. It takes about 50% of the sting out of the lash. It most definitely shifts better when warm than PTX. At 10 C shifting into 1st and second get a bit stiff but then something strange happens. The other oils including PTX get stiffer as they get colder. Millers starts to get stiff at 10 C but then gets no stiffer all the way down to -8 F. Which is as cold as the car has gone so far. I have used Millers EE exclusively for almost 10,000 miles and everything is just peachy keen. The only things special about PTX other than its viscosity is that it is overloaded with very expensive viscosity modifiers which dilute the oil's friction reducing capability and Mobil has a marketing deal with Porsche. If you don't like marketing deals and you are paranoid about using other oils by all means go with the Spirax.

Glad you like it, but we have had customer's that had zero luck with it.

That is right JFP. They were using the wrong oil. The EE just came out. They were using the racing formulation which came out several years ago. It has a spec very similar to the Delvac. (yuk) Go to Millers web site and check it out. Millers made the EE just for our transaxles and the stuff is nuts. I have absolutely no interest in Millers by the way.

Did you disagree with anything I said above??

  • Moderators
Posted

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

With respect to your comment "But N to 1st often needs a throttle blip to allow the teeth to engage at all" and general issues regarding shifting, especially in 1st and 2nd gears, you might want to read up on the following link. It's not only for pop-outs (that's the extreme case) and you should not be having any trouble with 1st or 2nd. They should be just as smooth as 3, 4, 5, and 6.

http://www.gboxweb.com/detent.html

Also, disagree that these transmissions are not good. They are good transmissions but you have to be careful with them and only use the OEM spec fluids, etc. They are not forgiving when you don't.

Silver TT, these transmissions are not bad they are just not as good as the G50 made by Getrag. I have just finished a 1 and 1/2 year experiment using 5 different transmission oils in my car through all the weather conditions we have up here in New England and I will be posting a DIY on transmission oil changing including all of the results of this experiment. It took so long because I had to use all the oils in winter conditions and it took two winters to get them all in. In most circumstances but not all, Millers is the best and my personal favorite. But, you are welcome to chug along with PTX. That is why Howard Johnson's made 28 flavors.

A34735, when someone tells you something that is wrong they are full of it. I myself have been full of it on occasion. I am with you on the voltmeter but the water temp gauge is important. As you have noticed there is a lag between oil temp and water temp. This is because the oil is down in the sump where the water is hopefully not. Going the other way, if your car starts to over heat, under some circumstances you will see it sooner in the water temp

Wouldn't ever think of putting anything but the OEM PTX in the gearbox. I have first-hand experience with the damage this will cause. $6K for a gearbox rebuild, or you can buy a reman from Porsche for $10K (before labor). The OEM PTX is an oil which is unique in that it literally has properties that no other oil has. Using the non-OEM will cause wear inside the gearbox over time (some people notice right away, in other cases this can take many thousands of miles). A lot of things people do with their cars I think are obsessing more than anything else, but with this topic I know first hand that if you use anything but the OEM gear fluid, you're asking for trouble.

+1 I have to agree with Silver_TT on this one. While some have gotten away with using aftermarket gear oils in these gearboxes, most have not. Problems have ranged from pronounced noise, to poor shifting, and actual mechanical failure problems. Considering the cost of either rebuilding or replacing these gear boxes, and the simple fact that the OEM lube is a full synthetic made to Porsche specs and not an API "GL" catagory, it seems counter intuitive to start playing around. The OEM product is readily availiable, not all that expensive, and works very well.

Take a deep breath. OK.

What makes these transmissions special is they are transaxles. The transmission and the hypoid final drive are in the same case. The transmission itself is the rather standard constant mesh synchronized transmission which Porsche was the very first to introduce in the 1952 356!! I'm sure JFP knows the deal well. For those of you who do not check this out http://www.youtube.com/watch?v=vOo3TLgL0kM . The problem with the transaxle designs is that hypoid final drives generate a lot of friction and require heavier lubes. Syncromesh transmissions do not like their oil to thick or the baulk rings do not clutch correctly, they float. Revs don't match up and you can't get the car in gear. So, what Porsche did was spec a gear lube that is at the very thinnest of the SAE 75W90 range with a very high Viscosity index. The higher the viscosity index the less the oil's weight changes with temperature. The oils had to have a cSt less than 600 at 0 C. The first to meet that spec was Shell with what was then called Shell Transaxle. It is now called Spirax S5 ATE which you can get in 20 liter drums. Ferrari uses it in their transaxle cars. Porsche use to use it but then Mobil made a marketing deal with Porsche. Thus Mobilube PTX (Porsche TransaXle) was born. These two are the only 75W 90 gear oils that meet Porsche's entire spec. The problem with them is that they are very thin when warm. Why a problem you ask??

All of these transaxles have a degree of drive train lash. Individual cars better or worse depending on luck and the weather. My car is a bit worse in this department. Don't believe me?? Next time you have your car up, put it in gear with the e-brake off. Grab a rear wheel and rotate it back and forth. You will have between 5 and 10 degrees of free play. That is the lash. You can feel it when you drive. Rapid large transitions on an off the gas produce a "thunk" which you feel in seat of your pants. Drive with the window down. You will also notice a lot of transmission noise as say compared with an Audi manual. This stuff is what got me started.

Science and specs tell us what to do. An SAE 90 oil can have a viscosity of any where between 13.8 and 18.8 cSt at 100 C. PTX is 14.5 cSt with a viscosity index of 194 (perfect is 200) Spirax is pretty much the same. All the other oils except Millers are around 15.5 cSt at 100 C with a viscosity index ranging from terrible like Delvac at 140 up to Redline at 176. Millers is special because their EE Nano oil has a viscosity of 17.8 at 100 C with a viscosity index of 183.

These oils perform exactly as you would expect. With the exception of Millers none of the oils do much to soften the lash and quiet the transmission. Delvac is just plain stupid below 10 C. If you try to jam the car into gear you might score the dog teeth on your syncro rings.

Until the transmission reaches full temp, which can take a while, shifting with Delvac ranges from poor to worse. The other oils are OK if you live and drive in environments that are always over 15 C. But if you live and drive anywhere where the Temp drops below 0 C Stick to the PTX or Spirax with ONE exception.

Millers is an interesting British company that has been around for a while making lubricants for industrial machines. In the last decade they started getting into motorsports and recently started formulating synthetic oils with nano particles. These particles have been absolutely proven to lower friction by up to 25%. All the science is available on-line. The stuff is very expensive. The gear oil got me to try the motor oil which I now use.

Anyway, The Millers most definitely quiets the transmission enough so that even my wife notices it. It takes about 50% of the sting out of the lash. It most definitely shifts better when warm than PTX. At 10 C shifting into 1st and second get a bit stiff but then something strange happens. The other oils including PTX get stiffer as they get colder. Millers starts to get stiff at 10 C but then gets no stiffer all the way down to -8 F. Which is as cold as the car has gone so far. I have used Millers EE exclusively for almost 10,000 miles and everything is just peachy keen. The only things special about PTX other than its viscosity is that it is overloaded with very expensive viscosity modifiers which dilute the oil's friction reducing capability and Mobil has a marketing deal with Porsche. If you don't like marketing deals and you are paranoid about using other oils by all means go with the Spirax.

Glad you like it, but we have had customer's that had zero luck with it.

That is right JFP. They were using the wrong oil. The EE just came out. They were using the racing formulation which came out several years ago. It has a spec very similar to the Delvac. (yuk) Go to Millers web site and check it out. Millers made the EE just for our transaxles and the stuff is nuts. I have absolutely no interest in Millers by the way.

Did you disagree with anything I said above??

I can only go by the feed back I get from customers; and those that tried the Millers line had a lot of complaints,particularly about low temperature performance (shifting was number one, followed by noise), in very low temp conditions (0F to 10F) where the products was supposed to excel. Another common comment was about the prices they paid for the Millers, but that has to be taken into account with their obvious displeasure on how the product performed. I also do not know, other than from what they told us, which product's were installed as we were not involved in that end of the process. I have noted, however, that you seem to see multiple types of Millers products with rather confusing designations, almost as though Millers might be doing some kind of "private label" deal with certain distributors of their products, which can also make both selection and comparisons difficult.

One comment I will make is that we have tended to stay with the OEM Shell product rather than the Mobil version, and the Burmah TAR 21 for the early Boxsters.

Posted

Their web site is...British. But what you describe is exactly what will happen if people put Millers CRX 75W 90 in their 911 transaxles. This is the racing version that has been around a while. People think that if you use a racing product that this is somehow better. WRONG.

Racing cars operate at a very steady HIGH temp. Their utmost concern is friction reduction. The high additive concentrations required to get a high viscosity index cut the oils lubricity. In our transaxles we have to balance the needs of the hypoid final drive with those of the transmission in a much wider variety of conditions. Millers developed the EE 75W 90 oil for this reason. It was released June 2013.

Millers does divide its site into Motorsports and road car categories but, it is easy to navigate to the wrong spot.

The stuff is expensive. This is not such a big deal for the gear oil as you don't change it often but the motor oil is $186 per oil change and that is very steep for just about everyone and the guys who can afford it probably don't change their own oil.

As far as I know Millers does not do any private label stuff but they have a lot of categories which makes things confusing. There is race stuff, road stuff, classic car stuff, Synthetic stuff, not so synthetic stuff and on and on. You have to love the British. They can't make a production car worth a toot but they do make the best race cars in the world.

Silver TT you need to calm down. Nothing in this life is black and white. No oil, not even Delvac will break dog teeth like that. Only severely uncoordinated and forceful movement of the left foot and right hand (for us Americans) will do that.

I suggest you have a beer ;-) I suppose it could have been a bad casting.

Posted (edited)

I'm sorry you think I have come across as upset or otherwise not calm. Don't get me wrong, it's your car and your money and this is a free country; you can do whatever you want and I have no problem with that.

But this is a moderated site and comments like yours need to be caveated. If you want to run a non-OEM oil in your transaxle, that's fine. But you're doing so at an increased risk of causing damage that will be very expensive if it does in fact occur. Aside from your tests over the last 10K miles, if you do your homework on this you will see that there are a number of people who had to figure this out the hard way. Shoot, just call Stan at Gbox and ask him about it since he sees these things every day for a living and has been doing so for the last 30 years. He has seen everything under the sun with Porsche gearboxes and no one is more qualified to opine on this topic than he is. You saying "they probably got sand in it" just isn't a constructive response or one that makes it very interesting to have a conversation with you.

The last thing is that those teeth aren't "broken". That's what metal-on-metal wear looks like when you don't have proper lubrication.

Edited by Silver_TT
Posted (edited)

Silver TT, understood. Now, the very interesting thing about humans is that if they don't know what is going on they make stuff up. You see this with very complex subjects like medicine and oil physics. You are not making stuff up. You have made a good decision based on what you were told and perhaps some 1st hand experience. I am neurotic enough to want to know exactly what is going on thus the lengthy research, experimentation and explanation. I would like every one to know about oil. There is a lot of marketing baloney out there.

Again, the wear on those teeth is absolutely not from oil. When the dogs are engaged there is absolutely no friction as they are locked. The duration of engagement is miniscule as compared to the constant rubbing and meshing of gears. Notice the gear teeth in your picture are pristine. Shifting technique did that perhaps with the addition of bad metalurgy say if the teeth were not hardened correctly. Excuse me. If you were using an oil like Delvac and lived and drove in a cold environment. Shifting in to first and second gears is going to be rediculously stiff. If you insisted in jamming your shifts in spite of this you might do that kind of damage with prolonged use particularly if you heard a brief "crunch" as the dogs engaged. A smart person would immediately ditch the oil which is exactly what I did as it became PAINFULLY obvious that that oil is DEFINATELY not for our transmissions unless you only used the car for racing with an always HOT transmission. The hot viscosity of PTX and Delvac are not that much different. Both are Mobil synthetic lubes by the way. Delvac was engineered for Caterpillar Tractors.

Dog teeth are engineered to take a certain amount of abuse. We all miss the occasional shift. Those teeth were subject to repetitive crunching.

Edited by Mijostyn

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