Dreaded RMS leak

[eDoug]

Hi there -

I just purchased an '02 996 C2 with 30k miles about a month ago. Since then, I've put about 2k miles on it, driven it hard, and noticed two things today. 1) I'm hearing some sort of rattle, maybe bearing noise, somewhere lower in the engine. Could be alternator, water pump, but it sounds further forward than that - maybe something near the bell housing? 2) For the first time, in the month, I just found a bit of oil on the garage floor - so looks like RMS failure. It appears as though there's a bit of oil on the underside of the engine, just behind the rear sway bar - looks like a drip from the end of an exposed bolt right in the center? Is this indicative of the RMS leak?

So I had the car thoroughly inspected with a PPI, and the RMS was checked. Perhaps the prior owner was just too gentle on the car!

The good news is that it's Porsche CPO'd and I'm looking forward to having that peace of mind... the bad news is it can't help but make you paranoid when anything fails on a high-end car. Also, it's the simple pain in the *** of having to deal with it...

In a nutshell, I couldn't be happier with the car - it drives wonderfully, the options are great, the engine sounds amazing, especially hitting 6k or so at WOT, then dropping it into 4th gear - just awesome. The handling is unparalleled - I've been driving Bimmers for the past decade or so and I've always been a proponent of "balance" and neutral handling - but this car breaks all the rules, in such a great way. The traction is amazing... So - I'm not unhappy with my choice, the cost of having a used car is this kind of frustration, and the savings, well, of course I paid half of the sticker price with 30k miles.

I'm not sure what I'm looking for here - besides a few word of encouragement, and perhaps any suggestions on the rattling noise. Seems as though this started about the same time I saw some oil on the garage floor, the past 2 days. If nothing constructive - then no worries, and I look forward to being a contributor on the board in the future.

Cheers,

eDoug

:renntech:

Edited July 29, 2008 by eDoug

[KevinMac]

Hi there -

I just purchased an '02 996 C2 with 30k miles about a month ago. Since then, I've put about 2k miles on it, driven it hard, and noticed two things today. 1) I'm hearing some sort of rattle, maybe bearing noise, somewhere lower in the engine. Could be alternator, water pump, but it sounds further forward than that - maybe something near the bell housing? 2) For the first time, in the month, I just found a bit of oil on the garage floor - so looks like RMS failure. It appears as though there's a bit of oil on the underside of the engine, just behind the rear sway bar - looks like a drip from the end of an exposed bolt right in the center? Is this indicative of the RMS leak?

So I had the car thoroughly inspected with a PPI, and the RMS was checked. Perhaps the prior owner was just too gentle on the car!

The good news is that it's Porsche CPO'd and I'm looking forward to having that peace of mind... the bad news is it can't help but make you paranoid when anything fails on a high-end car. Also, it's the simple pain in the *** of having to deal with it...

In a nutshell, I couldn't be happier with the car - it drives wonderfully, the options are great, the engine sounds amazing, especially hitting 6k or so at WOT, then dropping it into 4th gear - just awesome. The handling is unparalleled - I've been driving Bimmers for the past decade or so and I've always been a proponent of "balance" and neutral handling - but this car breaks all the rules, in such a great way. The traction is amazing... So - I'm not unhappy with my choice, the cost of having a used car is this kind of frustration, and the savings, well, of course I paid half of the sticker price with 30k miles.

I'm not sure what I'm looking for here - besides a few word of encouragement, and perhaps any suggestions on the rattling noise. Seems as though this started about the same time I saw some oil on the garage floor, the past 2 days. If nothing constructive - then no worries, and I look forward to being a contributor on the board in the future.

Cheers,

eDoug

:renntech:

You sure it's not the IMS, rattling could mean a broken Intermediate shaft

[Loren]

A broken water pump impeller sounds very much the same.

I would get an engine stethoscope and see if you can id the location of the noise.

[eDoug]

A broken water pump impeller sounds very much the same.

I would get an engine stethoscope and see if you can id the location of the noise.

Loren - great suggestion - it's hard to describe the noise, it is very erratic, sometimes it seems more frequent, but it's always non-uniform - can only hear it at idle with the windows down. Any faster RPMs and it seems to either be masked by engine/exhaust, or it goes away.

My guess would be water pump impeller as you suggest or maybe something in the oil sump??? Car runs great, pulls hard, nothing else noticeable.

Any thoughts on urgency if it's indeed the water pump?

Yeah, I know - hell it's under warranty - so I should just take it in immediately, but there's a long story there... it's not around the corner.

[Loren]

A broken water pump impeller sounds very much the same.

I would get an engine stethoscope and see if you can id the location of the noise.

Loren - great suggestion - it's hard to describe the noise, it is very erratic, sometimes it seems more frequent, but it's always non-uniform - can only hear it at idle with the windows down. Any faster RPMs and it seems to either be masked by engine/exhaust, or it goes away.

My guess would be water pump impeller as you suggest or maybe something in the oil sump??? Car runs great, pulls hard, nothing else noticeable.

Any thoughts on urgency if it's indeed the water pump?

Yeah, I know - hell it's under warranty - so I should just take it in immediately, but there's a long story there... it's not around the corner.

When the impellers start to break and fall off they get circulated in the cooling system and engine - engine temperature usually goes up.

In a few cases the water pump bearing goes and then all you have is the noise until it fails in a big way.

[eDoug]

Uh-oh! Guess it was a good thing I've been monitoring this noise - my local mechanic supposed it could be the pulleys/rollers making the odd clunk or tapping noise (he only gave me a quick opinion). I drove another 25 miles or so, then it got loud, very loud, about 1/2 mile from home. I coasted to the neighborhood - still thinking it was a pulley that gave out - and noting the temp was normal and oil pressure was normal - I went about 1/10th of a mile to my garage under power - the noise had subsided.

I got out of the car, and about 15 seconds passed before I heard the terrifying sound of oil freely draining onto the garage floor. Cleanup wasn't fun, a few gallons of oil - more importantly what happened???

I've gotta say, I've been driving the car somewhat hard for the past 2k miles over the last month (not bouncing the rev limiter or anything), and it was probably a bit of a garage queen with only 30k on the clock after 6 years - but still! All I can guess is that the RMS gave up, in a catastrophic way! Perhaps the intermediate shaft seals? I dunno - feel free to speculate. Here are some pictures of the aftermath.

It IS a CPO car, so I'm not crying in my beer, I can always hope for a new powerplant... but as a matter of interest and perhaps debate... Yes, I still love this car - just feeling fortunate that I have the warranty.

Edited July 31, 2008 by eDoug

[KevinMac]

Uh-oh! Guess it was a good thing I've been monitoring this noise - my local mechanic supposed it could be the pulleys/rollers making the odd clunk or tapping noise (he only gave me a quick opinion). I drove another 25 miles or so, then it got loud, very loud, about 1/2 mile from home. I coasted to the neighborhood - still thinking it was a pulley that gave out - and noting the temp was normal and oil pressure was normal - I went about 1/10th of a mile to my garage under power - the noise had subsided.

I got out of the car, and about 15 seconds passed before I heard the terrifying sound of oil freely draining onto the garage floor. Cleanup wasn't fun, a few gallons of oil - more importantly what happened???

I've gotta say, I've been driving the car somewhat hard for the past 2k miles over the last month (not bouncing the rev limiter or anything), and it was probably a bit of a garage queen with only 30k on the clock after 6 years - but still! All I can guess is that the RMS gave up, in a catastrophic way! Perhaps the intermediate shaft seals? I dunno - feel free to speculate. Here are some pictures of the aftermath.

It IS a CPO car, so I'm not crying in my beer, I can always hope for a new powerplant... but as a matter of interest and perhaps debate... Yes, I still love this car - just feeling fortunate that I have the warranty.

Looking at the last pic, it's been leaking for sometime!

[eDoug]

Looking at the last pic, it's been leaking for sometime!

If "some time" means LESS than a week, I guess you're right. :rolleyes: The car underwent a full CPO inspection just last week. I know that CPO doesn't guarantee finding everything, but they won't certify a car with a leaking gasket like that and I was underneath it a few days ago. I'd guess that I saw a few drops on Monday, followed by a bit more oil on the garage floor Tuesday. Yesterday, I drove for about 10-20 miles and absolutely dry garage.... until I arrived home today.

Oil is about 3k miles old.

Does anyone know if this is indicative of an RMS, or intermediate shaft seal? Also, if it's intermediate shaft, does that mean the engine is hosed, or is that repairable, too?

Thanks.

[Loren]

If it was a loud banging noise then chances are it is a broken intermediate shaft (sorry).

[eDoug]

If it was a loud banging noise then chances are it is a broken intermediate shaft (sorry).

So strange, because the car never lost power, and it was never running without oil... but it was pretty loud at idle for about a minute. If a broken intermediate shaft means they'll likely replace the engine (under CPO), then I should be pleased, right???

Thanks - appreciate the insights.

[KevinMac]

If it was a loud banging noise then chances are it is a broken intermediate shaft (sorry).

So strange, because the car never lost power, and it was never running without oil... but it was pretty loud at idle for about a minute. If a broken intermediate shaft means they'll likely replace the engine (under CPO), then I should be pleased, right???

Thanks - appreciate the insights.

That's exactly what I thought previous post. The reason I say for some time the areas that are wet are also caked which indicates oil and road dirt mixing over time. It would not surprise me the inspection was not thoughly done! It has been mentioned from others on this board. that these inspections depending on the dealer were not done to the full extent.

The good news is they certified it!

[eDoug]

That's exactly what I thought previous post. The reason I say for some time the areas that are wet are also caked which indicates oil and road dirt mixing over time. It would not surprise me the inspection was not thoughly done! It has been mentioned from others on this board. that these inspections depending on the dealer were not done to the full extent.

The good news is they certified it!

Thanks Kevin - perhaps you're right, but I was under the car a few days back from the same vantage I took the picture, and it looked "dry." I think you're just noticing the fresh oil mixing with the existing road scum. In any case, you're right about the warranty - and I'm keeping my hopes up that they'll do all the right things to get me back in action.

And just so folks know, this isn't a thread for me to ***** and moan about quality, etc. I understand the mechanical risk, particularly in buying a lower mileage car. I've also had plenty of things go wrong in the past with autos... This remains as one of the most fun cars in memory, and since I won't be robbing the college funds to buy a new engine (hopefully), I have little to complain about! If this happened out of warranty - I can't say it wouldn't put me off - but we'll have to wait to see the mechanic's diagnosis tomorrow...

I look forward to spending some time on the forum, and hopefully offering some helpful perspectives in the future. Thanks again for the insights.

Cheers - will post outcomes once I know more.

[KevinMac]

That's exactly what I thought previous post. The reason I say for some time the areas that are wet are also caked which indicates oil and road dirt mixing over time. It would not surprise me the inspection was not thoughly done! It has been mentioned from others on this board. that these inspections depending on the dealer were not done to the full extent.

The good news is they certified it!

Thanks Kevin - perhaps you're right, but I was under the car a few days back from the same vantage I took the picture, and it looked "dry." I think you're just noticing the fresh oil mixing with the existing road scum. In any case, you're right about the warranty - and I'm keeping my hopes up that they'll do all the right things to get me back in action.

And just so folks know, this isn't a thread for me to ***** and moan about quality, etc. I understand the mechanical risk, particularly in buying a lower mileage car. I've also had plenty of things go wrong in the past with autos... This remains as one of the most fun cars in memory, and since I won't be robbing the college funds to buy a new engine (hopefully), I have little to complain about! If this happened out of warranty - I can't say it wouldn't put me off - but we'll have to wait to see the mechanic's diagnosis tomorrow...

I look forward to spending some time on the forum, and hopefully offering some helpful perspectives in the future. Thanks again for the insights.

Cheers - will post outcomes once I know more.

Well sorry it came down to such a dreaded situtation, but i am sure it will work out in the end. Keep up posted,and welcome! Much luck in getting this resolved!

[perryinva]

Yes, from the forums, dealers have been putting in new remanufactured by Porsche engines under CPO. The RMS and IMS are right over each other, so your leaks were probably IMS all along. Failed IMS that causes oil to pour out is destroyed engine. I HATE this, as I own a 2002 C2 Coupe with 40k miles, and it is NOT CPO, and I I bought it in March of this year. So far, it's been perfectly quiet and dry. I just changed the oil to Mobil1 0w-40, and it eliminated some niggling issues, like feeling the Variocam plus at 3200 rpm, and some lifter ticking at idle. The old oil only had 5k miles & 8 months on it and was Mobil 1 but unknown viscosity, so I decided to change it, and VERY glad I did. Can I ask what you paid for the car, with the CPO warranty and where you're located??

If it was a loud banging noise then chances are it is a broken intermediate shaft (sorry).

So strange, because the car never lost power, and it was never running without oil... but it was pretty loud at idle for about a minute. If a broken intermediate shaft means they'll likely replace the engine (under CPO), then I should be pleased, right???

Thanks - appreciate the insights.

[eDoug]

Thanks - appreciate the insights.

I checked the receipt and the dealer had put in 15x50 Mobil 1 at last oil change. Was planning to change it after the Summer, but alas, I didn't need to do that. Just needed to mop up a few gallons from the garage floor and then the street once the flatbed wrecker showed up and we pushed it to the street. I will definitely not run that viscosity in the future, as it's not THAT hot here.

Sent a PM regarding price (roughly, in the $41k range). Thanks for the good wishes - I'll keep my fingers crossed for a new engine, and will post back once I hear from the dealer.

[KevinMac]

Thanks - appreciate the insights.

I checked the receipt and the dealer had put in 15x50 Mobil 1 at last oil change. Was planning to change it after the Summer, but alas, I didn't need to do that. Just needed to mop up a few gallons from the garage floor and then the street once the flatbed wrecker showed up and we pushed it to the street. I will definitely not run that viscosity in the future, as it's not THAT hot here.

Sent a PM regarding price (roughly, in the $41k range). Thanks for the good wishes - I'll keep my fingers crossed for a new engine, and will post back once I hear from the dealer.

Wow a Porsche dealer put in an oil that was not on the recommended Porsche oil list?

[judgejon]

Thanks - appreciate the insights.

I checked the receipt and the dealer had put in 15x50 Mobil 1 at last oil change. Was planning to change it after the Summer, but alas, I didn't need to do that. Just needed to mop up a few gallons from the garage floor and then the street once the flatbed wrecker showed up and we pushed it to the street. I will definitely not run that viscosity in the future, as it's not THAT hot here.

Sent a PM regarding price (roughly, in the $41k range). Thanks for the good wishes - I'll keep my fingers crossed for a new engine, and will post back once I hear from the dealer.

Wow a Porsche dealer put in an oil that was not on the recommended Porsche oil list?

15-50 is on the list... am I missing something here?

[eDoug]

15-50 is on the list... am I missing something here?

At the risk of starting another "oil wars" thread :oops:

The December 2007 Porsche approved oils list doesn't have anything more viscous than 5W-50 as far as I can tell. Given that cold starts are a major wear issue on any engine - the "Mobile Water" seems like a good cold start oil, and the rating to a 40 weight when hot should provide ample protection - given it's the factory fill also.

I've tended to run heavier oils when given the option in the past - because I also tend to drive hard. However, after reading and understanding the issues with engine tolerances, and multiple service duties (like oil acting as a hydraulic fluid for variocam), etc., I'll stick with the Porsche approved oil list. You can find it under the 996 TSBs if you're a member, and search for "Oil."

Oh, and I received a remanufactured engine, courtesy of the Porsche CPO warranty, after my intermediate shaft (bearing) failed.

[KevinMac]

15-50 is on the list... am I missing something here?

At the risk of starting another "oil wars" thread :oops:

The December 2007 Porsche approved oils list doesn't have anything more viscous than 5W-50 as far as I can tell. Given that cold starts are a major wear issue on any engine - the "Mobile Water" seems like a good cold start oil, and the rating to a 40 weight when hot should provide ample protection - given it's the factory fill also.

I've tended to run heavier oils when given the option in the past - because I also tend to drive hard. However, after reading and understanding the issues with engine tolerances, and multiple service duties (like oil acting as a hydraulic fluid for variocam), etc., I'll stick with the Porsche approved oil list. You can find it under the 996 TSBs if you're a member, and search for "Oil."

Oh, and I received a remanufactured engine, courtesy of the Porsche CPO warranty, after my intermediate shaft (bearing) failed.

I haven't seen 15W-50 on the list. I used Castrol 5w-40 Porsche approved, since where I live I don't need to go down to the 0W. I don't think I have ever seen 5W- 50 being sold off the self! Maybe available on the net.

Edited September 3, 2008 by KevinMac

[function12]

Any news on you car?

[judgejon]

15-50 is on the list... am I missing something here?

At the risk of starting another "oil wars" thread :oops:

The December 2007 Porsche approved oils list doesn't have anything more viscous than 5W-50 as far as I can tell. Given that cold starts are a major wear issue on any engine - the "Mobile Water" seems like a good cold start oil, and the rating to a 40 weight when hot should provide ample protection - given it's the factory fill also.

I've tended to run heavier oils when given the option in the past - because I also tend to drive hard. However, after reading and understanding the issues with engine tolerances, and multiple service duties (like oil acting as a hydraulic fluid for variocam), etc., I'll stick with the Porsche approved oil list. You can find it under the 996 TSBs if you're a member, and search for "Oil."

Oh, and I received a remanufactured engine, courtesy of the Porsche CPO warranty, after my intermediate shaft (bearing) failed.

I haven't seen 15W-50 on the list. I used Castrol 5w-40 Porsche approved, since where I live I don't need to go down to the 0W. I don't think I have ever seen 5W- 50 being sold off the self! Maybe available on the net.

Kevin, I checked the TSB and you're right. but 15-50 is noted in my owners manual. I live in a cooler climate area, but travel to high temp inland areas often. that's why I'm using the 15-50. seems the heavier 5w would be a harder cold weather start. I used Castrol 20-50 in my SC for years with no problem. would you recommend a different oil at the next change? Cheers, jl

[eDoug]

Kevin, I checked the TSB and you're right. but 15-50 is noted in my owners manual. I live in a cooler climate area, but travel to high temp inland areas often. that's why I'm using the 15-50. seems the heavier 5w would be a harder cold weather start. I used Castrol 20-50 in my SC for years with no problem. would you recommend a different oil at the next change? Cheers, jl

Okay - one thing to get straight - the winter spec (0w-40) refers to viscosity when cold (there's more to it, I know). The 0 weight is thinner than a 5 or 15 weight when starting the engine at, let's say, room temperature (although the spec is at 0 degrees celsius). This means that it also circulates more quickly and covers the valve train, etc. regardless of the temperature. Hence, a thinner oil can reduce cold-start wear moreso than with a thicker oil which takes more time to penetrate and circulate to and through the tight engine tolerances.

I used to think you'd be crazy to run "thinner oil" but after reading lot's of threads, books, and conducting what I'd call "independent research" - I'm sold on using the factory fill in these engines. 5W-40 doesn't give any better warm-weather or high-temp protection than 0w-40, and it offers less cold-start protection.

So 'splain it to me Lucy - why use thicker oil unless you're spending a day at the track, running hard from dawn until dusk and not letting the engine cool down appreciably??? Not inviting flames - but interested in any intelligent reasoning.

[1999Porsche911]

15-50 is on the list... am I missing something here?

At the risk of starting another "oil wars" thread :oops:

The December 2007 Porsche approved oils list doesn't have anything more viscous than 5W-50 as far as I can tell. Given that cold starts are a major wear issue on any engine - the "Mobile Water" seems like a good cold start oil, and the rating to a 40 weight when hot should provide ample protection - given it's the factory fill also.

I've tended to run heavier oils when given the option in the past - because I also tend to drive hard. However, after reading and understanding the issues with engine tolerances, and multiple service duties (like oil acting as a hydraulic fluid for variocam), etc., I'll stick with the Porsche approved oil list. You can find it under the 996 TSBs if you're a member, and search for "Oil."

Oh, and I received a remanufactured engine, courtesy of the Porsche CPO warranty, after my intermediate shaft (bearing) failed.

I haven't seen 15W-50 on the list. I used Castrol 5w-40 Porsche approved, since where I live I don't need to go down to the 0W. I don't think I have ever seen 5W- 50 being sold off the self! Maybe available on the net.

Kevin, I checked the TSB and you're right. but 15-50 is noted in my owners manual. I live in a cooler climate area, but travel to high temp inland areas often. that's why I'm using the 15-50. seems the heavier 5w would be a harder cold weather start. I used Castrol 20-50 in my SC for years with no problem. would you recommend a different oil at the next change? Cheers, jl

A 50 viscosity oil is best for your Porsche and 15W or 20W is perfectly fine unless you are regularly starting your engine when the oil temperature is below freezing. For some reason, many educated people here argue that 15W50 or 20W50 are too thick an oil to get to into the "tight tolerances" of the engine. I would love to know just one oiled area of the engine that has any tigher tolerance than any high compression engine from 40+ years ago.

For those who rely on Porsche to tell them what is alright to do, 5W50 is approved and if this oil has no problem going through the engine, then neither will a 15W or 20W oil. Porsche continues to factory fill their TIGHT engines with Mobil 0W40 and many of these cars burn gallons of oil between changes and leak from various orifices. The use of 0W40 from the factory is primarily due to substantial subsidy to Porsche from Mobil as well as Porsche's need to meet epa and other regulator's demands for better fuel economy. In most cases, moving to a better oil reduces or eliminates both oil burning and leakage as well as provides better shear protection, especially at low rpm torque conditions, better lifter operation at both idle and near redline, etc, etc.

[judgejon]

Kevin, I checked the TSB and you're right. but 15-50 is noted in my owners manual. I live in a cooler climate area, but travel to high temp inland areas often. that's why I'm using the 15-50. seems the heavier 5w would be a harder cold weather start. I used Castrol 20-50 in my SC for years with no problem. would you recommend a different oil at the next change? Cheers, jl

Okay - one thing to get straight - the winter spec (0w-40) refers to viscosity when cold (there's more to it, I know). The 0 weight is thinner than a 5 or 15 weight when starting the engine at, let's say, room temperature (although the spec is at 0 degrees celsius). This means that it also circulates more quickly and covers the valve train, etc. regardless of the temperature. Hence, a thinner oil can reduce cold-start wear moreso than with a thicker oil which takes more time to penetrate and circulate to and through the tight engine tolerances.

I used to think you'd be crazy to run "thinner oil" but after reading lot's of threads, books, and conducting what I'd call "independent research" - I'm sold on using the factory fill in these engines. 5W-40 doesn't give any better warm-weather or high-temp protection than 0w-40, and it offers less cold-start protection.

So 'splain it to me Lucy - why use thicker oil unless you're spending a day at the track, running hard from dawn until dusk and not letting the engine cool down appreciably??? Not inviting flames - but interested in any intelligent reasoning.

Thanks much. I had my numbers wrong. the lower first number is the thinner, duh. considering what you've mentioned, I'll likely go with the 5w-40 at next oil change just on general principles. question: why would Porsche list the 15w-50 in the 2003 owners manual? why not have that multi-vis oil still on the approved list? thanks, j

[judgejon]

15-50 is on the list... am I missing something here?

At the risk of starting another "oil wars" thread :oops:

The December 2007 Porsche approved oils list doesn't have anything more viscous than 5W-50 as far as I can tell. Given that cold starts are a major wear issue on any engine - the "Mobile Water" seems like a good cold start oil, and the rating to a 40 weight when hot should provide ample protection - given it's the factory fill also.

I've tended to run heavier oils when given the option in the past - because I also tend to drive hard. However, after reading and understanding the issues with engine tolerances, and multiple service duties (like oil acting as a hydraulic fluid for variocam), etc., I'll stick with the Porsche approved oil list. You can find it under the 996 TSBs if you're a member, and search for "Oil."

Oh, and I received a remanufactured engine, courtesy of the Porsche CPO warranty, after my intermediate shaft (bearing) failed.

I haven't seen 15W-50 on the list. I used Castrol 5w-40 Porsche approved, since where I live I don't need to go down to the 0W. I don't think I have ever seen 5W- 50 being sold off the self! Maybe available on the net.

Kevin, I checked the TSB and you're right. but 15-50 is noted in my owners manual. I live in a cooler climate area, but travel to high temp inland areas often. that's why I'm using the 15-50. seems the heavier 5w would be a harder cold weather start. I used Castrol 20-50 in my SC for years with no problem. would you recommend a different oil at the next change? Cheers, jl

A 50 viscosity oil is best for your Porsche and 15W or 20W is perfectly fine unless you are regularly starting your engine when the oil temperature is below freezing. For some reason, many educated people here argue that 15W50 or 20W50 are too thick an oil to get to into the "tight tolerances" of the engine. I would love to know just one oiled area of the engine that has any tigher tolerance than any high compression engine from 40+ years ago.

For those who rely on Porsche to tell them what is alright to do, 5W50 is approved and if this oil has no problem going through the engine, then neither will a 15W or 20W oil. Porsche continues to factory fill their TIGHT engines with Mobil 0W40 and many of these cars burn gallons of oil between changes and leak from various orifices. The use of 0W40 from the factory is primarily due to substantial subsidy to Porsche from Mobil as well as Porsche's need to meet epa and other regulator's demands for better fuel economy. In most cases, moving to a better oil reduces or eliminates both oil burning and leakage as well as provides better shear protection, especially at low rpm torque conditions, better lifter operation at both idle and near redline, etc, etc.

this entire discussion is very interesting and this last post is very reassuring. still curious about why 15w-50 is in the 2003 book, but I'm thinking that for those of us who do not live in more radical climates the higher ranges of oil noted are going to be ok. thanks to all...

Edited September 3, 2008 by judgejon