Chevrolet Cruze Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
62 Posts
Discussion Starter · #1 ·
I have a 6MT 1.4T.. I was driving tonight and when I down shifted from 2000RPM in 3rd gear down to 2nd gear, which takes it up to about 3200RPM in 2nd and it popped out of gear. Then I started to test it a little bit and I was able to redline it accelerating in 2nd but as soon as i let off the accelerator it would pop out of gear. After messing around for a few minutes I found out that it only pops out of gear when I reach 3k RPM or higher. Under 3k RPM it does NOT pop out.

I think some of the problem might be from trying to shift from first into second and the gears grinding with a cold start that has happened at least 10 times throughout the past year and a half of owning the car.

My buddy seems to think it might be the hydrolics or the syncronizer...

I'm not sure if I explained it clearly enough, but if you have any questions or hopefully some answers for me PLEASE let me know.
 

·
Administrator
Joined
·
25,596 Posts
I would take it in. These cars don't slip out of gear like this. Since you can repeat it take your service adviser on a test drive and demonstrate it.
 

·
Premium Member
Joined
·
3,975 Posts
I'd bet it's a worn 2nd gear synchronizer. If the backside of the synchronizer teeth get too worn, it can let the transmission pop out of gear if the gear loading changes. How many miles on it?
 

·
Administrator, Resident Tater Salad
Joined
·
17,346 Posts
I've heard this before, mostly from Sonic folks. Yup, synchros. Take it in and get it fixed under warranty, then switch fluids to something thicker (Id try Amsoil 75w-90 for the way you drive) so it doesn't happen again.


Sent from AutoGuide.com App
 

·
Premium Member
Joined
·
249 Posts
Probably need a new trans. A few member on SOF had this happen.

For atleast one case the cause was determined the plastic tip on the shift fork falling off was the cause. With the tip now off there was more play between the shift fork and engagement collar (that locks the gears together), the slop would allow the collar to slip off during certain loads such as letting off the throttle. When that happens the trans can pop out of gear.

Also a missing shift tip can affect gear engagement for the gear set It's affecting. This could be why you've had some extra grinding going on. Although given this trans predisposition to grind under certain conditions with certain fluids it may not be the cause of your recent grinding.


It's not the only possibility for your symptoms but it is a likely candidate. The only fix GM has regardless of the issue is to throw a new trans at it.
 

·
Premium Member
Joined
·
249 Posts
Found the thread on it. Post #14
M32 Trans Teardown - Chevy Sonic Owners Forum

As for the tune, yes flash back to stock. It's improbable that they'll check for a tune with this issue, several members here and on SOF have gone in still tuned and had the trans replaced no problem, usually for the 2nd gear grind.

And yes this is covered under your 5yr 100k mi powertrain warranty. When you do get your new trans in be sure to put in a better fluid like the Amsoil 5w-30 syncromesh before too long. It'll protect your trans longer, alleviate the occasional 2nd gear grind, and keep shifts smooth well beyond when the stock fluid gets notchy.
 

·
Registered
Joined
·
62 Posts
Discussion Starter · #11 ·
Found the thread on it. Post #14
M32 Trans Teardown - Chevy Sonic Owners Forum

As for the tune, yes flash back to stock. It's improbable that they'll check for a tune with this issue, several members here and on SOF have gone in still tuned and had the trans replaced no problem, usually for the 2nd gear grind.

And yes this is covered under your 5yr 100k mi powertrain warranty. When you do get your new trans in be sure to put in a better fluid like the Amsoil 5w-30 syncromesh before too long. It'll protect your trans longer, alleviate the occasional 2nd gear grind, and keep shifts smooth well beyond when the stock fluid gets notchy.
Thank you! I have an appointment set up for Monday to get it checked. I will keep everyone posted on what caused it and probably a video so people with the same problem will understand.

Sent from AutoGuide.com Free App
 
1 - 12 of 12 Posts
Top