Topic: Synchros

[ryansalazan]

I am under the impression that alot of people have some issues when it comes to the synchros after about 50k miles. Well I'm starting to have a little bit of issues at 75k. I just wanted to know if anyone has replaced synchros? If so, what part numbers did you purchase from the dealership? I've heard that all synchros should cost vroughly around 300-400 dollars. and Since i'm going to have to take the transmission out again for the clutch I might as well do it.

[ryansalazan]

Also I did want to note that I do have a bunch of different part numbers on a list for different parts of the transmission, however, I'm not exactly sure what is the synchro or part that I'm needing. If anyone had an illustration as well that would help. As of right now, I'm understanding that I'm in need of the synchro hub?

[DaveOC]

Also I did want to note that I do have a bunch of different part numbers on a list for different parts of the transmission, however, I'm not exactly sure what is the synchro or part that I'm needing. If anyone had an illustration as well that would help. As of right now, I'm understanding that I'm in need of the synchro hub?

Maybe this will help you:

http://parts.nalleygmc.com/showAssembly.aspx?ukey_assembly=389463&ukey_make=1030&ukey_model=14651&modelYear=2009&searchString=transmission+synchros

[Sol Asylum]

To replace the syncros you will basically be rebuilding the transmission.  It's not a simple remove and replace a single part, you will have the transmission almost completely disassembled.  If you don't know what your doing you could cause a lot more problems than you solve.

[ryansalazan]

Yes this is true. I have a friend of mine that I help out with business and hes helping me out with the transmission work. What I'm ultimately trying to figure out is what are all of the exact parts that I would need to replace synchros and how much will it be? Because if it is too much, then I would just buy a lightly used transmission. lol

[ryansalazan]

Maybe this will help you:

http://parts.nalleygmc.com/showAssembly.aspx?ukey_assembly=389463&ukey_make=1030&ukey_model=14651&modelYear=2009&searchString=transmission+synchros

Very useful! Thank you for this find. It looks like its going to almost be about $450-550... Might as well just start looking into a lightly used transmission I had an eye on. Maybe cryo treat all of the components while its out too.

[Sol Asylum]

See if Elff still has this trans, he's upgrading to the 6 speed from DDM.

[GXP_Matt]

I'm at 50k and my second gear synchro seems to be in pretty bad shape. I have to wait like 2 seconds between 1 and 2 for the revs to drop enough to get a clean shift.  It seems to me like the rev hanging that GM programmed into the engine calibration dooms the synchros if people don't wait for the revs to drop when shifting.  Mine were crunchy since I bought the car at 30k...

[ryansalazan]

are you sure the rev hanging has something to do with the way the car is tuned? I have a tune in my car and the revs dont really seem to hang that much once the clutch is pressed. I now have a lightweight flywheel and it doesn't hang up in the revs at all. I'm thinking it actually might have something to do with the really heavy weight of the stock flywheel? That thing weight like almost double to triple what the lightweight one weighs.

[wspohn]

I find that if you pause between shifts (standard on British cars) you actually get more balking than if you just pull through smoothly - not slamming, but firmly.  The feel on these gear boxes is certainly far from the best I've experienced.

[ryansalazan]

I will agree on that! ^^^^

[GXP_Matt]

are you sure the rev hanging has something to do with the way the car is tuned? I have a tune in my car and the revs dont really seem to hang that much once the clutch is pressed. I now have a lightweight flywheel and it doesn't hang up in the revs at all. I'm thinking it actually might have something to do with the really heavy weight of the stock flywheel? That thing weight like almost double to triple what the lightweight one weighs.

I hadn't heard that before, good to know.