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-   -   997.2 6spd transmission problem (https://rennlist.com/forums/997-forum/1140066-997-2-6spd-transmission-problem.html)

neckthrough 04-24-2019 05:48 PM

997.2 6spd transmission problem
 
The problem
I have a 2010 997.2 C2S 6spd with 36K miles that is currently under CPO. Every once in a while the transmission refuses to go into 1st gear. Re-clutching or shifting into 2nd and then 1st usually solves the problem. As you can imagine, it creates some panic moments at traffic lights as I'm attempting to drive off on a green. Here are some more specifics:
1). This has nothing to do with general notchiness when the car is cold. The problem usually occurs once the car is nicely warmed-up and the transmission is otherwise shifting smoothly.
2). This may just be statistical variance - but the frequency of the problem seems to be higher in warm weather.
3). Needless to day, I made certain the clutch was completely depressed.

Here are some videos that I was able to take when the problem occurred in a parking lot.

The following video was taken last Friday (April 19, 2019). The weather was around 75F. The car was parked outside and had been off for ~3 hours. I sat inside, pushed the clutch in, pulled the transmission into neutral, started the motor, let the clutch out, idled for a minute or so, pushed the clutch back in and then tried to put the car into 1st gear to drive off. This is what happened:
https://drive.google.com/open?id=1Mn...R3Wps9mJCfdddY

This next video was taken last year in late May 2018. In this case I had just pulled *into* my office parking lot after my commute, so the engine, transmission etc. were completely warmed up.
https://drive.google.com/open?id=110...rRXnESzdwd6vo7


Experience with Dealership #1
I posted about this on a regional thread on these forums (https://rennlist.com/forums/new-engl...sion-work.html). Here is a quick summary: The dealership acknowledged and reproduced the problem. They said there were metal traces in the transmission fluid, which could be evidence of a failing synchro. However, since that diagnosis they have been stalling me for nearly the past year with a variety of excuses. I've spoken to the service manager in person, over the phone, over email countless times and it's always some stall. Now here's the problem - my experience with this dealership on other unrelated issues does not give me a ton of confidence in their ability to work on something as complex as a transmission. And so I set about trying to find another dealership.

Experience with Dealership #2
The head tech took a test drive. He concluded it was "user error" and the transmission was performing as it should. To his credit, it was a cold day, and I had not encountered the problem either on the drive to or from the dealership. I also started hoping that maybe the problem was something temporary and went away on its own. Unfortunately that was not the case - it reappeared (again, could be correlated with the exterior temperature, or maybe just my frequency of driving which was a lot lower in winter). I followed up with the service manager, and he is understandably unwilling to take any further steps without being able to reproduce the problem (my videos notwithstanding). I suggested that we could do a transmission fluid change (at my expense) to see if there were telltale signs of anything. He gave me a quote of $700-something for the work, which seems a little absurd. He also added that any metal traces in the fluid would be insufficient evidence to start any repairs, so that was back to square one.

Experience with PCNA
PCNA were extremely courteous. They suggested proceeding with Dealership #1 and in fact went ahead and spoke to the service advisor on my behalf, then contacted me again and asked me to set up an appointment with them. I contacted Dealership #1, and.... stall (I'll get back to you next week/month/Friday).

What I'm thinking now
Basically I'm channeling Hamlet. My warranty is about to expire in a little over 1 month. Dealership #2 has been telling me there's nothing wrong with my car - and they are definitely seem to be more technically capable than #1. They probably didn't encounter the problem, but perhaps it's possible that they are right? Did #1 mis-diagnose the issue and are now trying to back-pedal (hence all the stalling)? In which case I wouldn't want anyone to open up the transaxle - that's a recipe for untold future disasters. But when I'm at a traffic light and 1st gear just straight up jams up I'm not so sure any more. Last summer this happened around 1 every 4 times, so it's not rare. I can push all my weight on top of Dealership #1 (via PCNA if necessary) but I'm worried that they may screw something up.

I would appreciate any feedback or advice. Please take a look at the two videos. Again, those were taken in parking lots (because it was safe to take a video), but the problem can show up anytime I'm shifting into 1st gear.

Thanks for your time folks.

SFZ GT3 04-24-2019 06:34 PM

Sorry to read this, it must be frustrating on many levels. A couple things to thnk about:

1. Have you tried releasing the clutch and then depressing again with another first gear try? Maybe it needs a bit of "rotational motion" to find first a little easier.

2. Try touching second within a small time after clutch pedal being depressed as a force of habit, I do that now and have for years. It works well in my current (new to me 997.2 GTS).

3. Has either dealer suggested adjusting/replacing the shifter cables? Seems like low mileage for that, but who knows how the previous owner "handled" the shifter and shift action. Worth a try for sure.

Good luck and I hope it's a simple fix. Keep us posted.

C4SDayton 04-24-2019 07:00 PM

Happens once or twice a week to me 08C4S. Happens usually when warmed up, but majority of miles is after warm up. Usually when get to light and sit there a minute or two, although don't think time sitting at all relevant. Depress clutch a second time or quick shift into second then into first while clutch in usually does it. Give it a nice hard shove when in more of a hurry sometimes. I think dealer 2 was right, not the user error part, just that not a problem to try to fix now. Don't go for too much of manual trans fluid voodoo as far as what is root cause of issue. I'm starting to accept some idiosyncrasies. It is once in a while you said, so chuck it in second occasionally when happens and ride a little clutch, can't be worse than my spouse in first gear:)

Hula 04-24-2019 07:05 PM

Have you heard of Mobilube PTX? It's a Porsche approved transmission oil that is a popular "solution" for the 1st gear lockout. Lots of threads on this board so I won't go into the details.

https://www.suncoastparts.com/product/00004320420L.html

bml376 04-24-2019 07:23 PM

I have a 2012 997.2 6MT with ~39K miles and this happens for me sometimes as well. My car is mainly a track car, only driven on the street to/from the track. I've been using Mobil 1 Delvac 75w-90 and replace the gearbox fluid after ~6 track days. I've also had my gearbox oil sent off for UOA (used oil analysis), report is below. They indicate from testing that the wear metals were "remarkably low". So I guess wear metal amount might not be the cause of the issue, as like I said, it happens to me intermittently. I've also never seen metal when replacing my fluid.



https://cimg2.ibsrv.net/gimg/rennlis...ab19935a4c.png

tanger 04-24-2019 07:28 PM

I have this issue too, haven't gotten around to changing out the tranny fluid. I have found that depressing clutch and moving the lever first into 2nd then back into 1st will usually do it, or actually shifting into 2nd, letting clutch out and creeping a bit will then open up 1st. Or just go from 2nd.

hapa997 04-24-2019 07:40 PM

This happened to me on my old 997.1 quite a bit, even after changing the transmission fluid. According to my local indy shop, this was one of the symptoms of a worn clutch. The other symptoms are 1) a high clutch release point, and 2) a heavy clutch pedal. Once he swapped in a new clutch, this problem went away, and would only occasionally happen when the car was ice cold. Once it warmed up though, everything was fine. Hope this helps...

Qwksnke 04-24-2019 07:42 PM


Originally Posted by tanger (Post 15796616)
I have this issue too, haven't gotten around to changing out the tranny fluid. I have found that depressing clutch and moving the lever first into 2nd then back into 1st will .

I don't have a manual porsche but pretty much all manual performance cars I have ever owned, I have had to do this as well

shyamvenky 04-24-2019 07:52 PM

Another that I've read in the forums is to rev the engine a little bit (slightly higher than idle) to help shift it into 1st.
I think it was a post from Petza (thanks again for all the wisdom) - reasoning was that it is at that slightly higher rpms that the gears mate better.
Mine is a 997.1 6spd with 96k miles and I got the transmission fluid changed recently - it did help in general, but I do still see the jam, rarely though.

Carreralicious 04-24-2019 07:56 PM

This happens on my 07S 997.1 as well sometimes (28k miles on it currently). If it happens, I just put it into 2nd and then into 1st. If that doesn’t work, I just start off in 2nd. Or, I just down shift into 1st as I’m rolling into the stop light prior to a full stop. That way, you know 1st will be available cause it is already in that gear when you are finally stopped. If anything, I think it’s a matter of a cable adjustment and not the fluid or clutch. I agree it’s annoying, but it doesn’t happen all the time. It never happened on my Boxster though (and I never once changed the tranny fluid in the 17 yrs I owned it).

BillNye 04-24-2019 08:31 PM


Originally Posted by SFZ GT3 (Post 15796466)
Sorry to read this, it must be frustrating on many levels. A couple things to thnk about:

1. Have you tried releasing the clutch and then depressing again with another first gear try? Maybe it needs a bit of "rotational motion" to find first a little easier.

2. Try touching second within a small time after clutch pedal being depressed as a force of habit, I do that now and have for years. It works well in my current (new to me 997.2 GTS).


Originally Posted by Hula (Post 15796543)
Have you heard of Mobilube PTX? It's a Porsche approved transmission oil that is a popular "solution" for the 1st gear lockout. Lots of threads on this board so I won't go into the details.

https://www.suncoastparts.com/product/00004320420L.html

Both of these.
I had this problem pretty frequently as well. When the clutch has been disengaged long enough for the input shaft to stop spinning it can occasionally be difficult to get the sychro teeth to self-align. Either going into 2nd gear first, or letting the clutch back out slightly while in neutral will move things around enough to usually allow the gear to engage.
Switching to the mobilube PTX was quite a noticeable improvement as well. Between a little discipline about how/when I engage first and the new fluid I rarely encounter the issue.
If you're handy it's worth a $110 to do the fluid change yourself and see if you notice a difference.

C4SDayton 04-24-2019 09:13 PM

If there were metal traces in fluid, does that mean dealer 1 changed fluid? If so, to what?

Greg2010 04-25-2019 01:47 AM

I have a 997.2 manual that occasionally is hard to shift into 1st after stopping in traffic. This seems to occur at random (cold or hot). I agree that a small blip of the throttle or a slight tug into 2nd then first helps to resolve (but I wonder if a cable adjustment or engine mount replacement would help).

Petza914 04-25-2019 09:17 AM

Also, from under the car, check that the shift cables are properly retained in their little grooves. If they are, get some wire ties and secure them in there. I'd they're not, pop them back in and then wire tie them into place so they can't pop out.

If I were having this issue, here's how I'd look to resolve it in this order.
  1. Check that the shift cables are properly retained under the car
  2. Change the transmission fluid with Mobillube PTX and don't think about using anything else - nothing works as well in this transmission
  3. Check the motor and transmission mounts

If none of these things resolve the issue, then you'll either have to use one of the workarounds mentioned in these posts (2nd then first like in your videos, clutch out and back in again, a blip of the gas when not holding the shift lever against the sticking point) or have someone open up the transmission as it sounds like the 1st gear synchro may be worn or you could also have a clutch about to go bad (less likely if it's not exhibiting any other odd behavior than this.

Also, it doesn't have to be second gear you use - any gear will stop the input shaft from spinning and the second gear synchro probably sees more use and wear than any other gear, so I'd actually recommend using a different one with that method, like 3rd.

The tech at dealership #2 isn't correct - they don't all do this and they don't do it 25% of the time. Neither of my 997s have this problem. My wife's had it sometimes, but the change of the gearbox oil with PTX has resolved it and her car (and transmission) have 105k miles on it, also a SSK that is supposed to make the problem worse, and her clutch is really stiff compared to mine, so probably about worn out (have one in the parts cabinet), and with all of this, the move into 1st at a stop works just fine.

Bruce In Philly 04-25-2019 02:07 PM

2009 C2S 133K miles

1st gear jam.... known issue..... I just change the fluid every 35K wit PTX... read here:

https://rennlist.com/forums/997-foru...-gear-oil.html

Peace
Bruce in Philly


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