Transmission grinding woes
Thread Starter
Advanced
Joined: Feb 2016
Posts: 86
Likes: 9
From: Tualatin, OR
Transmission grinding woes
I have an 03 Z06 which has been having some transmission problems. Under WOT, the 1-2 shift grinds every time. Under normal driving conditions 1-2 shift is fine, however sometimes it takes a bit more effort to get it to go into 2nd, but only sometimes. Also, the 4-3 downshift grinds at anything above ~40mph (2500ish rpm I think?). Below this it never seems to grind. Also about half the time, when you put it into reverse and slowly relase the clutch, it will grind and you'll have to take it out of reverse and put it back in again.
I've tried readjusting the shifter using froggy's video when I had a c6 shifter and then the MGW tool when I got the MGW shifter. It seems to help a little bit maybe but not really. I've cycled the fluid in the master cylinder using the ranger method and got it nice and clear but didn't seem to do anything either. Are the syncros in the tranny just toast? Or do you think the clutch isn't disengaging all the way? Any ideas would be great. Thank you!
I've tried readjusting the shifter using froggy's video when I had a c6 shifter and then the MGW tool when I got the MGW shifter. It seems to help a little bit maybe but not really. I've cycled the fluid in the master cylinder using the ranger method and got it nice and clear but didn't seem to do anything either. Are the syncros in the tranny just toast? Or do you think the clutch isn't disengaging all the way? Any ideas would be great. Thank you!
Thread Starter
Advanced
Joined: Feb 2016
Posts: 86
Likes: 9
From: Tualatin, OR
Any ideas?? Thought I'd add the clutch is stock with 64k miles on it (transmission too). Also regarding the reverse issue, the 50% that it grinds when letting the clutch out, when on a downhill and just letting it roll, the shifter will vibrate pretty noticeably. When I take it out of reverse and then put it back in again, there aren't any vibrations and no grinding when I let the clutch out.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
When was the last time that you checked and changed the clutch master cyl fluid? I bet its low and black and nasty.
Give that a look see and do the ranger flush procedure.
Bill
Give that a look see and do the ranger flush procedure.
Bill
Racer
Joined: Mar 2014
Posts: 345
Likes: 86
From: Goodlettsville Tennessee
How many miles are on the car?
Mine started the 1-2 grind at about 85K.
I'm not saying it's related, but when I switched to RP syncromax, My 1-2 shift started grinding shortly after. The shifter adjustment helped for a couple of weeks, but then the grinding returned.
In my case the 1-2 syncro was gone, so I ended up doing a tranny rebuild and replaced all snycros, keys, and bearings. with this kit:
http://www.hawksmotorsports.com/t56-...d-kit-package/
Just wanted to prepare you for the worst, as it sounds like your syncros are done.
Mine started the 1-2 grind at about 85K.
I'm not saying it's related, but when I switched to RP syncromax, My 1-2 shift started grinding shortly after. The shifter adjustment helped for a couple of weeks, but then the grinding returned.
In my case the 1-2 syncro was gone, so I ended up doing a tranny rebuild and replaced all snycros, keys, and bearings. with this kit:
http://www.hawksmotorsports.com/t56-...d-kit-package/
Just wanted to prepare you for the worst, as it sounds like your syncros are done.
Thread Starter
Advanced
Joined: Feb 2016
Posts: 86
Likes: 9
From: Tualatin, OR
I tried the ranger flush method maybe 1k miles ago and it didn't seem to make any difference. I'll give it another go though, perhaps I didn't do it completely.
Car has 64k miles on it. I bought it at 60k, so I don't know how it was treated before that.
Car has 64k miles on it. I bought it at 60k, so I don't know how it was treated before that.
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Instructor
Joined: Jul 2016
Posts: 207
Likes: 23
From: Atlanta, Ga
Price depends on what area your in really. I pulled the trans out myself and took it to a shop and they charged me $1850.00 to rebuild my t-56, had a bad 3-4 syncro. Had them upgrade to billet keys as well. I thought it was very expensive to be honest with you. By the way I'm in Atlanta, G.A
Burning Brakes
Joined: Jul 2013
Posts: 935
Likes: 103
Price depends on what area your in really. I pulled the trans out myself and took it to a shop and they charged me $1850.00 to rebuild my t-56, had a bad 3-4 syncro. Had them upgrade to billet keys as well. I thought it was very expensive to be honest with you. By the way I'm in Atlanta, G.A
At the same time on a previous vehicle I opted to go the used transmission route, on the test drive after install I discovered the trans did not have 3rd or 4th gear
You get what you pay for but yes $1850 seems like Corvette Tax...(Which is nothing compared to Viper Tax... ask me how I know)
OP It sounds like it might be a syncro or could be a bent shift fork??
Last edited by Roddy13; Sep 23, 2016 at 01:07 PM.
Instructor
Joined: Jul 2016
Posts: 207
Likes: 23
From: Atlanta, Ga
Yep, the way I know how to check and see if the clutch is fully disengaging is to get in your car push clutch in start engine up, put trans in 1st gear and rev engine up to about 5500 rpm's. If the car moves any at all your clutch is not disengaging all the way. When you do this test make sure car is parked on a flat surface and don't have your e brake pulled up either.