Clutch stuck in first/reverse intermittently

[Trevnerdio]

Hey guys, pretty new to this forum as far as posting goes, but here goes...

I've got a problem that's going to make me pull my hair out. My M6 2013 2LT, when hot outside (especially in traffic) get stuck in first and reverse. The only remedy without yanking that sucker clean out is shutting off the engine and restarting it in neutral, or "jumping" the thing out of gear (feign a stall, but slam clutch pedal down before RPMs bottom out).

Some back story
Early in 2016, I got my slipping, crap OEM clutch replaced with a SPEC stage 1 clutch and aluminum single mass flywheel. Things started getting weird - it would start to get stuck both in gear, and lock me out.

What I've tried so far (which is absolutely absurd for an issue like this)

• Replaced both clutch and flywheel again with brand new SPEC products at a different mechanic
• Changed transmission oil over to Amsoil 75W-90 from Redline
• Replaced clutch slave with new OEM
• Replaced clutch master with Ideal Garage product
• GOT A COMPLETE TRANSMISSION REBUILD
• Got a new clutch shipped from SPEC (this time UNsprung, because the springs totally fell out of my previous one...), free of charge. Flywheel cleaned up

And would ya guess it, here I still am, probably $4000 later, trying to not ruin my transmission for a second time.

Note: It shifts absolutely beautifully on cooler days (80 and below, but Tallahassee gets hot as hell) and it no longer gets locked out of gear since the rebuild...at least not yet.

So whatcha guys got?? You've been lifesavers before, I seent it!

[camguynj]

So there is never any problem in traffic when it's 80 or below ?

[Trevnerdio]

Originally Posted by camguynj

So there is never any problem in traffic when it's 80 or below ?

Nope, seems fine. I've also tried changing out brake fluid several times, forgot to mention that. And even wrapped exhaust pipe, thinking maybe it was boiling the fluid.

[camguynj]

OK so just to clarify ... there is no problem when 80 or below even in stop/go traffic ? If that's the case then hot clutch fluid can be ruled out as it would get just as hot in stop/go traffic regardless of temp. Still wouldn't hurt to install a braided SS clutch line and siwtch to DOT4 fluid.

[Trevnerdio]

Originally Posted by camguynj

OK so just to clarify ... there is no problem when 80 or below even in stop/go traffic ? If that's the case then hot clutch fluid can be ruled out as it would get just as hot in stop/go traffic regardless of temp. Still wouldn't hurt to install a braided SS clutch line and siwtch to DOT4 fluid.

I had already switched to Motul 600 DOT4, even went as crazy as 660 once... Still no change. My last hope is SS braided line. I should mention that it most often happens when I rev it a bit and slip the clutch to move up in traffic. Upon putting the pedal back down, it just continues pulling, like it's half engaged.

[tonyG]

sounds like your clutch is not fully disengaging . Im having a similar issue but maybe someone with more experience can chime in

[RankSS]

Sure sounds like the slave is not shimmed correctly.

[camguynj]

Originally Posted by RankSS

Sure sounds like the slave is not shimmed correctly.

^^^^^

[Trevnerdio]

Originally Posted by RankSS

Sure sounds like the slave is not shimmed correctly.

What does shimming do? And why wouldn't my mechanic have thought about that? �� Dude's cost me a lot of money so far...

[camguynj]

Originally Posted by Trevnerdio

What does shimming do? And why wouldn't my mechanic have thought about that? �� Dude's cost me a lot of money so far...

Here's a great explanation of what it is and why its needed. Ask your mechanic if he did?
https://ls1tech.com/forums/manual-tr...need-shim.html

[Trevnerdio]

Originally Posted by camguynj

Here's a great explanation of what it is and why its needed. Ask your mechanic if he did?
https://ls1tech.com/forums/manual-tr...need-shim.html

Thanks so much! I'm going to bring this up with him and see what he says.

[camguynj]

Here's an illustration of how to do the measurements https://cdn6.bigcommerce.com/s-ao78k...356396.jpg?c=2

[Trevnerdio]

Hey guys, thanks so much for the replies. Talked to a dude at AAMCO today, seemed pretty arrogant. Said he had never heard of "shimming a slave cylinder" before. Is this just a bandaid fix or is it a recognized practice? Didn't care for the guy's demeanor. Thoughts?

[luisortiz21]

Hey guys, so I had the same problem with my 2013 V6 . I also installed the Spec 1 clutch with the aluminum flywheel. I also replace the master cylinder and slave cylinder at the same time with a short shifter. After the problem occur right away maybe a day or two after it was installed I thought the slave cylinder failed. So I have a shop open and back up and reinstall a new one it worked yet again another day or two then continue to get stuck in reverse and first gear. Then it hit me I think it's overthrowing the clutch. So I ordered this part https://www.phastekperformance.com/R.../ram-78305.htm to adjust the pedal height so I don't over engage the throwout bearing. Since the car didn't come with the height adjuster this was the best bet. Just installed it last week and hasn't got stuck at all. The only thing there's a dead spot in the very beginning but it's definitely worth it if you installed the Spec 1 and have this problem. I also think I'm going to replace the slave cylinder one more time I just feel like it destroys it the first day or two since it worked fine Everytime I replace it. I hope this helps