Feeling Gear Very Slight Grinding But Intermittently

[spyhunter]

Hey everybody,

First, it is great to be on this alias and I am glad that I have come across it. Second, I want to state in advance that I am both a novice to Porsche (I just bought my first one) and I am only an intermediate level driver.

Here is my story. I recently bought a certified pre-owned 2007 Carrera 2S from the dealer. It has been a while since I have driven a manual, so perhaps I did not notice this the first couple of days when driving the vehicle.

After driving for a few days I started to notice that every now and then when I shifted into second (and sometimes when I shifted into third, but less often) that I did not hear a grinding noise, but I could feel in the shifter that gears or something else were lightly brushing against each other before I went into gear. Other times the shifting would be smooth. It is almost as if the clutch was not pushed down all the way, but I am pushing down that clutch as far as it will go.

Also, the feeling I feel is like a faster whirl slowing down making me think it is the gear teeth or something, but again I am not an expert on transaxles.

I took it to the dealer and one of the techs drove it. They said everything was fine and that I would feel the gears sometimes a little bit harder to get into and this was normal. As far as the brushing feeling, the tech said that I had a new clutch and that I had to make sure to push it down all the way.

Yeah, at first I was going to buy all of this, but after I thought about it some more, there are some red flags in all of this.

First, a short shifter was installed not too long ago in the vehicle before I purchased it. Second, this is a C2S with sport chrono, sports exhaust in addition to the shifter. Yeah, kinda makes me think that someone who is getting all of that might have the desire to be more aggressive with the car.

What I did see in some forums is to drive another pre-owned 911 or a new 911 to feel the difference.

I did read the other forums and saw the info on transmission fluid and syncros, it is just difficult in my case because it is intermittent and I don't hear the grinding, but I can feel the "brushing" of something against something else every now and then.

Am I just being paranoid here?? Is this slight brushing that I feel every now and then normal or could it belong in the grinding category??

The car has only 16K miles.

Again, I am thinking of just driving another pre-owned 911 or new 911 to compare, maybe that will help as well.

Thanks in advance for your help.

Edited April 21, 2010 by spyhunter

[355bhp]

Is the tranny warmed up, or does this happen when it's cold? I'm unfamiliar with the short shifter, but if this notchiness is on the downshift, practice double-clutching; it's faster, easy on the synchros, and lotsa fun!

[spyhunter]

I meant the sports shifter. . .

The "notchiness" is on upshifts and possibly downshifts, but I upshift more than I downshift. I don't downshift when coming to a stop light or stop, I take it out of gear and put it in neutral while I slow down and step on the break.

Only occasionally when I have to slow down for a turn and need to go into a lower gear, I will downshift, and I try to do a little rev-matching, however I haven't even thought about heel-toe at this point, I have to get comfortable with the basics first.

On another thread, it was asked if the grinding was at higher RPM's or lower RPM's and if lower RPM is smooth and higher RPM is not good, then this could be the synchros.

I still need to characterize that.

I just don't like the feeling of gear teeth or this "notchiness" even if I don't hear any grinding. I bought this car because I want the shifting experience to be as pleasureable as possible. Everything else about the car is fantastic, the handling, the response, the suspension, etc, so I was just hoping that the shifting would also be at that level as well.

I didn't buy a Porsche so it could shift like my old Jeep Wrangler did.

I just don't think any "notchiness" or feeling of something rubbing against something else seems acceptable. . .

I am going to go to the dealer to test drive a new 911 and I think this will really help to clarify things.

If it is my shifting or "just the way it is" then I will feel it in the new 911. And if it is completely smooth in the new 911, then something is not right I would think.

Anyway, thanks for the reply!!!

Edited April 22, 2010 by spyhunter

[phillipj]

I have had several Porsches and have never experienced what you are describing. Unles you expect a Porsche tranny to feel like a Toyota this is totally normal.

I have an 06 997 S with the standard shifter and it's smooth as silk. Maybe you just have to get used to the feel.

I think it's a good idea to go drive another 997 so you can rule out any issues with your car...

[355bhp]

You're right in that downshifting before a stop is totally not necessary (but--shh--sometimes I do it anyway, just for the fun of it), because the Porsche's brakes are so powerful, and pad changes are easy. Sometimes shifting too slowly will produce a soft grind, so try shifting with authority. You don't have to baby these cars. Oh, and welcome to the Forum!

Edited April 22, 2010 by 355bhp

[dphatch]

It is probably the way the shift cables are attached to the short shifter. The grinding occurs when the cables are attached at something other than the ideal points on both cables. When Porsche attaches the shift cables they use a very accurate tool that insures that the attachment point for both cables are dead on. If the car is CPO'd than ask the dealer to correctly adjust the shifter cables. If they won't do it or want to charge you lots of $$'s go to the B & M Shifters web site and download the installation instructions. They will explain how the cables attach to the shifter. From there it's a simply a matter of trail and error to get both cables correctly attached. Make a small adjustment, drive the car, make another small adjustment, drive the car. Thiis way You can not only get the grinding out you will also get better engagement from the shifter once you get the cable attachment points correct. When I installed the short shifter in the Boxster I left the center console on the bench until I got the shifter where I wanted it, then I re-installed the console. This makes the process much easier as you can actually make adjustments while you're pulled over on the side of the road without going all the way back to your garage. Make small adjustments so you don't wind up way off the correct setting. Not hard to do but not as easy as having the dealer do it for free.

[Hank]

I had the sport shifter installed (by the dealer -- wanted it done right) a couple of months after I bought my 2007 "S". It seems that it does make the shift feel a little "notchier," especially when cold, and the dealer warned that it is possible to shift so quickly that you can "beat" the syncros if you're not careful. But it is so much better overall and more fun that I could never go back.

You mentioned that you haven't had a stick shift car in a while; memory may be part of the problem. I don't think that anyone will ever get a modern car with a remote transmission and cables to shift like a 60's muscle car with an aftermarket Hurst shifter attached to the transmission case. But the rest of the car is sooooo much better that you really can't complain. These cars are great and we are all very lucky. Enjoy.

[spyhunter]

Thanks again everybody for replying. . .

I actually have numerous things I am going to do here and I will update everybody when I am done. . .

1) I joined PCA, I am going to talk to some PCA folks (which I'm sure a lot of you are as well). I am going to talk to PCA folks in my region and also let them check out the car and give their thoughts

2) I am going to take it to another dealer for a second opinion

3) I have a good friend who has worked in the automotive industry for 30 years coming down from Michigan to inspect the car as well in about two weeks

4) I still have to drive a comparable or newer 911

In the meantime, yes, I feel like a kid all over again, I can't get enough of driving the car. The adrenaline rush is amazing every time!!

I had the sport shifter installed (by the dealer -- wanted it done right) a couple of months after I bought my 2007 "S". It seems that it does make the shift feel a little "notchier," especially when cold, and the dealer warned that it is possible to shift so quickly that you can "beat" the syncros if you're not careful. But it is so much better overall and more fun that I could never go back.

You mentioned that you haven't had a stick shift car in a while; memory may be part of the problem. I don't think that anyone will ever get a modern car with a remote transmission and cables to shift like a 60's muscle car with an aftermarket Hurst shifter attached to the transmission case. But the rest of the car is sooooo much better that you really can't complain. These cars are great and we are all very lucky. Enjoy.

[mghorayeb]

Hi everyone,

I have an '06 Carrera S 6-speed with sport shifter (from factory). I experience the same issue ONLY when the car is cold, and then shifting from 3rd to 4th. If I insist on continuing to upshift, I feel the same grind (sometimes) in 5th and 6th. After it 'grinds' the first time (I feel it more than hear it), the issue is gone. Once the car is warm, there is no more issue. I (you) need to allow the oils to warm up before going into 4th, 5th, and 6th, and then there's no issue (note that I haven't called this a 'problem' because, at least in my case, I feel it is driver error/oversite). The car has less than 30K miles and had a recent minor service. I have been driving 911s for the last 20+ years. There really is no substitute.

...and this is an incredible site...full of knowledge and experience - once I sort out my Paypal, I will contribute and encourage others to do the same.

Mark, Dubai.

[PAULSPEED]

I would drain the transmission oil looking for metal parts.

You have a big race track and someone might have tried to drive

the course with out using the clutch.

Most professional drivers have problems shifting with out the

clutch.

Paul

[mxt_77]

I gotta say that there are some peculiar replies in here. Lol!

Personally, I'd start with the simplest attempt at a fix. Change your transmission fluid. According to my maintenance booklet, the interval is 120K miles on the trans fluid, but that just boggles my mind. I've never driven a vehicle with an interval greater than 30K miles, and I'd change it well below the interval on any car that was driven hard. I'm sure Porsche has a reason for indicating such a long interval, but I'm pretty sure some fresh fluid couldn't do anything but help. Plus, it'll give you a chance to ship the old fluid off for analysis to see if you really have any reason for concern.

I, too, have noticed much more resistance when shifting in this car compared to my previous vehicles, particularly when the trans is still cold. Two things that I've found which help are:

1) Don't let the revs drop too much. It seems this car has a relatively light flywheel and the revs drop more quickly than other vehicles I've driven. If they drop too much before you switch into the next gear, you're forcing the synchros to do more work bring the transmission back up to match the engine speed. From this perspective, "rev-matching" is important in downshifts as well as upshifts.

2) Figure out where the gear is, and don't force the shifter to go somewhere else. Personally, when I used to shift into second, I'd pull the gear to the left and continue pulling the shifter towards me as I moved it down into second gear, however I've found that it'll slide into 2nd more easily if I pull straight back once I get it far enough over to drop into 2nd.

Good luck! Please be sure to update us as your troubleshooting continues, especially if you find a solution.

[PAULSPEED]

I can just imagine me driving in the desert.

Down-shifting from 6th to 5th at 140MPH.

Or maybe on the Dubai Racetrack.

Paul

[mghorayeb]

Hi Paul,

It's not as glamorous as you think...There are radar units everywhere, and one needs to watch out for camels. Fortunately, we have several months of glorious weather ahead of us, because once Spring hits, it's already too hot/humid.

Anyhow, I was at Porsche yesterday, and have made an appointment to get some things tended to - I will also ask them to check transmission's cable linkage, since I felt a 5th gear 'grind' with warm gearbox and gentle shift a couple of days ago.

Drive safely,

Mark.

[mghorayeb]

Update: After clutch/pressure plate were recently changed (clutch was toast at end of last track day at Yas F-1 circuit in Abu Dhabi), the grinding problem was exacerbated, particularly going into 6th gear (to the point that I was double clutching going from 5th to 6th). My experience and instinct told me that this was a bad syncromesh, but I thought that was unlikely considering that syncro issues would show up in the lower gears (where there's more torque and use). I decided to have the transmission fluid replaced and the linkage checked before getting into more complex and $$$ issues inside the transmission. Long story short is that tranny fluid change made a HUGE improvement. Even though the car only has 55k kms on it, and Porsche recommends fluid changes every 120k kms, I felt that my spirited driving, occasional track day, and crazy Dubai Summer temperatures may have compromised the oil quality lots quicker than Zuffenhausen expected (or Japan for that matter, where these Aisin boxes were made). When I examined the old oil (and compared it to the new), it was slightly discolored, had a burned aroma, and was very thin (with viscosity akin to water). After a few days with the new oil, the entry into 6th gear is grind free - I have yet to try a lightning quick 5-6 change, but the improvement is substantial. I would recommend 997.1 manual drivers who live in hot climates make the change MUCH earlier than what Porsche recommends, and make sure you go easy on the gearbox until the new oil has a chance to get acquainted...

[S2Andy]

Hi everyone,

Thanks Mark, for the reassuring posts I just read.  Seems that these gearboxes have a few issues when cold but they are great once warmed up.  Agree it is the forward fill plug that is used to fill the gearbox.

I am new to 997 6-speed ownership although I have manual 944 S2, 928 S4 and 964 cars as well.  They all shift pretty well, even the S4 with 136k miles!

My '06 C2S has 80k kms (50k miles) and a standard shifter with quite long throws.  I've driven the short shift kits in 996's and I like the rifle bolt feel, they are very positive but no doubt harder on the synchros. 

In my 997, the shifts from 4th to 5th and 5th to 6th are notchy until the gearbox oil is warmed up (about four miles seems to be enough for clean 5th and slow shifts in to 6th)  First four gears shift well right from cold but I was concerned enough with the slow synchros into 5 and 6 to drain the trans today.  The old oil was darker in colour, and I found a few tiny bits of steel in the sump plug residue and collected a few more from the bottom of the gearbox with a magnet, but with 80km on the clock, this was nothing significant IMHO. 

I replaced the oil with 2.6 litres of ​PetroCanada 75-90 Synthetic, it was definitely thicker than the old fluid. (I have had good experience with this oil in my 944 racecar which handles very rapid shifting with no problems)

I then took it for a drive and the shifts into 5th and 6th seemed no better until the gearbox oil was a bit warmed up, but I will take the car for a longer drive to see if the oil getting around a bit more will improve the shifts earlier from cold.  If this doesn't work I I will try some Swepco 80-90, then after that it will be looking into synchro replacement as I don't like the faint crunch I hear at all!  I'll update this after a few more km on the new oil.