T56 oil leaks
Thread Starter
Racer
Joined: Mar 2011
Posts: 394
Likes: 58
From: lancaster MA
T56 oil leaks
So, my '03 Z06, w/26k miles, is leaking transmission fluid from where it connects to the Getrag. It's not a huge leak but I do notice a few drops overnight when it's parked in the garage. It appears that the black sealant that was used between the T56 and Getrag has failed. I say "appears" because I'm not convinced if it's really the culprit in this issue - isn't it truly the seal that surround the output shaft of the transmission that is to blame for this problem. If I remove the rear-end, which seal should I focus upon?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
On a T56, the OUTPUT shaft seal keeps the ATF inside the trans.
Are you sure that it is ATF that is leaking and not 90 weight lube because thats the only thing that can be in the void between the trans and the differential (unless you have an A4)
Are you sure that it is ATF that is leaking and not 90 weight lube because thats the only thing that can be in the void between the trans and the differential (unless you have an A4)
Thread Starter
Racer
Joined: Mar 2011
Posts: 394
Likes: 58
From: lancaster MA
Hi Bill - Welll, the fluid is red and doesn't have the stink I associate with rear-end fluid. If that output shaft seal does fail, wouldn't it leak into the void between the transmission and differential. Actually, the leak seems to be at the seam that's to the right (as one faces the passengers' side of the transmission) of the drain plug. I just drained the Dexron out and re-filled it with Pennzoil Sychromesh. While it was drained, I cleaned that seam, along the bottom and part ways up both sides, with acetone. I then smeared a thin layer of gas-tank sealant along the seam. I don't expect it to work but I have used that sealant on a gas tank while it was leaking and it did the trick for years! Eventually, I know I'm going to have to pull the rear-end off and fix it properly.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Yep,,,,,, Thats a transmission case leak. That part of the trans contains 5th & 6th gears& reverse gears.
Heres a post that shows you the disassembly and reassembly of a T56:
C5 ragtopws6, T-56 Build (whats in my tranny?) : http://forums.corvetteforum.com/nort...-smoother.html
The seam of that case is where you are leaking. You can easily remove that part of the trans and reseal it.
Bill
Heres a post that shows you the disassembly and reassembly of a T56:
C5 ragtopws6, T-56 Build (whats in my tranny?) : http://forums.corvetteforum.com/nort...-smoother.html
The seam of that case is where you are leaking. You can easily remove that part of the trans and reseal it.
Bill
Thread Starter
Racer
Joined: Mar 2011
Posts: 394
Likes: 58
From: lancaster MA
Thanks Bill! Those pictures in the T56 Build (what's in my tranny?) were very helpful. I didn't realize that the top two gears & reverse were in that part of the case. Looks like I'm going to have to locate the transmission repair manual next. I imagine one has to separate the diff' from the transmission before taking that rear case off. And, I should probably replace the seal on that output shaft, too?
Thread Starter
Racer
Joined: Mar 2011
Posts: 394
Likes: 58
From: lancaster MA
Thanks Bill. Well, it appears I've bought myself a little time. My trick with the Seal-All seems to be working. After letting the Seal-All cure for 24 hours, I took the Z' for a spin. I only drove the car about 10 miles (enough to get things up to operating temp's) and then inspected the joint. It's bone dry! I'll go for a longer drive this weekend and should have a better feel for the "repair" afterwards. I figure if I can go 100 miles, without any drops/spots appearing on the cardboard I have laying on my garage floor, I won't have to worry about pulling the rear-end off until this winter....
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