[Z06] Transmission leak...please help
Thread Starter
Advanced
Joined: Jun 2007
Posts: 54
Likes: 0
Transmission leak...please help
Ok, so I have been getting a small drop here and there on the floor for a while now and I finally decided to jack the car up and see what the deal is. Here are some pics:
Any thought on this? Why it would happen? What exactly is causing it?
Thanks
Any thought on this? Why it would happen? What exactly is causing it?
Thanks
Melting Slicks
Joined: Mar 2006
Posts: 2,754
Likes: 380
From: South Florida FL
Is it a slow leak?I had a similar leak, most likely where the case comes to together. you'll have to clean it real good, an look for the leak, might be a weekend project.
but the fluid only goes so far up in the case and its not pressurized.
Personally I put silicone on the outside of the case, the same GM silicone they use to seal the case and its been holding up fine. I'll fix it correctly when the trans comes back out.
but here's a pic so can have an idea of where to look.
if you look close enough, you can see the fluid just riding down that "valley" and settle at the button.
clean it good with brake cleaner etc. and silicone it from the outside, that may work temporarily. the correct way is resealing the case though.
but the fluid only goes so far up in the case and its not pressurized.
Personally I put silicone on the outside of the case, the same GM silicone they use to seal the case and its been holding up fine. I'll fix it correctly when the trans comes back out.
but here's a pic so can have an idea of where to look.
if you look close enough, you can see the fluid just riding down that "valley" and settle at the button.
clean it good with brake cleaner etc. and silicone it from the outside, that may work temporarily. the correct way is resealing the case though.
Last edited by FourG63 97GST; Dec 15, 2008 at 04:16 PM.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
I recently had my 02 Z06 at the dealership for a leak similar to yours.. The Service Tech said that there was a TSB issued for the rear Transmission housing.. The problem was in the casting/molding proceedure.. The housing was porous, thus just replacing the seal would not correctly solve the problem.. Rear trans housing and seal was replace under extended warranty... It would have been $1100 out of pocket if I did not have the extended warranty... And still we wonder why American car companies can't compete
Pro
Joined: Oct 2007
Posts: 564
Likes: 0
From: The Great Nation of North Carolina
My 01 has a very mild , one drop now and then weep. It's exactly like the photo right above. Fixing it will probably cause it to leak more ! I am going to do the Silicone thing that was stated above. I've never actually seen a drop though, When I wiped it , it stayed dry flonger than I was willing to look .
I have a piece of cardboard under the rear in the garage and can see if it is getting worse, it's not. In a period of a year there may be 12 or so spots on the cardboard.
t
I have a piece of cardboard under the rear in the garage and can see if it is getting worse, it's not. In a period of a year there may be 12 or so spots on the cardboard.
t
Last edited by only59; Dec 17, 2008 at 05:22 AM.
Instructor
Joined: Nov 2004
Posts: 148
Likes: 0
From: Denver CO
The photos Look like my '03 a couple years ago. There is a breather on top of the tranny that can leak, although the dealer's first response is "overfilled tranny". Thread a small mirror up there and verify the source. Also do a search on this fantastic forum for other ideas on the subject.
Thread Starter
Advanced
Joined: Jun 2007
Posts: 54
Likes: 0
The drops are very slow. It was once every week but now it appears to be up to once every couple days. Im selling the car but I don't believe in screwing someone over so I was curious as to how to take care of this issue in order to not have to lie to the buyer.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Advanced
Joined: Jun 2007
Posts: 54
Likes: 0
I recently had my 02 Z06 at the dealership for a leak similar to yours.. The Service Tech said that there was a TSB issued for the rear Transmission housing.. The problem was in the casting/molding proceedure.. The housing was porous, thus just replacing the seal would not correctly solve the problem.. Rear trans housing and seal was replace under extended warranty... It would have been $1100 out of pocket if I did not have the extended warranty... And still we wonder why American car companies can't compete
Thread Starter
Advanced
Joined: Jun 2007
Posts: 54
Likes: 0
If I keep the car for another 2 months I get a free clutch so maybe I can tackle the leak at the time of the clutch swap.
Melting Slicks
Joined: Mar 2006
Posts: 2,754
Likes: 380
From: South Florida FL
whats this stop leak you leak you're putting in the transmission?
i'm against any kind of stop leak, since it not only goes to the leak, but goes everywhere else you dont need it to be. is this stuff approved for out transmissions?
i'm against any kind of stop leak, since it not only goes to the leak, but goes everywhere else you dont need it to be. is this stuff approved for out transmissions?
Burning Brakes
Joined: Dec 2005
Posts: 882
Likes: 10
From: Bay Area CA
Is it a slow leak?I had a similar leak, most likely where the case comes to together. you'll have to clean it real good, an look for the leak, might be a weekend project.
but the fluid only goes so far up in the case and its not pressurized.
Personally I put silicone on the outside of the case, the same GM silicone they use to seal the case and its been holding up fine. I'll fix it correctly when the trans comes back out.
but here's a pic so can have an idea of where to look.
if you look close enough, you can see the fluid just riding down that "valley" and settle at the button.
clean it good with brake cleaner etc. and silicone it from the outside, that may work temporarily. the correct way is resealing the case though.
but the fluid only goes so far up in the case and its not pressurized.
Personally I put silicone on the outside of the case, the same GM silicone they use to seal the case and its been holding up fine. I'll fix it correctly when the trans comes back out.
but here's a pic so can have an idea of where to look.
if you look close enough, you can see the fluid just riding down that "valley" and settle at the button.
clean it good with brake cleaner etc. and silicone it from the outside, that may work temporarily. the correct way is resealing the case though.
I am planning on using roofing sealant. The same stuff that is used to seal flashing material. You can get the stuff at Home Depot.
Thread Starter
Advanced
Joined: Jun 2007
Posts: 54
Likes: 0
So I got under my car last night....the differential on the left side is leaking...BAD...and the transmission has gotten WAY worse. Guess I have to fix both now while I replace the clutch. Anyone have a guild to doing the transmission gasket? Or to pulling everything in general?
Thanks
Thanks
Racer
Joined: Aug 2009
Posts: 393
Likes: 1
From: Maynardville TN
I noticed from these pictures your transmissions don't have a "weep hole" so to speak in the rear transmission housing? Mine does and it is leaking from there.It is a LARGE leak. I leaked out 2 qts in 300miles and did not know it(just bought the car).
I dropped the crossmember/rear end thinking it was the output shaft seal in the transmission and the case had a weephole so the fluid wouldn't puddle in between the diff. and transmission, and would let you know you had a leak.BUT, The hole runs up a channel and to the FRONT side of the rear seal. The top of the transmission is dry it's coming from somewhere low.
Sorry for the ramble, any ideas?
I dropped the crossmember/rear end thinking it was the output shaft seal in the transmission and the case had a weephole so the fluid wouldn't puddle in between the diff. and transmission, and would let you know you had a leak.BUT, The hole runs up a channel and to the FRONT side of the rear seal. The top of the transmission is dry it's coming from somewhere low.
Sorry for the ramble, any ideas?
Burning Brakes
Joined: Jun 2004
Posts: 1,184
Likes: 3
From: KADS- If it has wings or an engine, I can break it. Dallas TX
Looks like it is coming from the front of the trans. Possible input shaft leak or possible leak from the engine. If it was leaking from the bottom of the trans, it wouldn't have oil on the front half of the case.
Check your clutch housing weep holes (slots on bottom) are they black? Could be leaking there and blowing back on the trans. Got a bad clutch ayy???
Check your clutch housing weep holes (slots on bottom) are they black? Could be leaking there and blowing back on the trans. Got a bad clutch ayy???
Burning Brakes
Joined: Jun 2004
Posts: 1,184
Likes: 3
From: KADS- If it has wings or an engine, I can break it. Dallas TX
I recently had my 02 Z06 at the dealership for a leak similar to yours.. The Service Tech said that there was a TSB issued for the rear Transmission housing.. The problem was in the casting/molding proceedure.. The housing was porous, thus just replacing the seal would not correctly solve the problem.. Rear trans housing and seal was replace under extended warranty... It would have been $1100 out of pocket if I did not have the extended warranty... And still we wonder why American car companies can't compete
Racer
Joined: Dec 2006
Posts: 4,434
Likes: 18
From: Braselton GA
drain the fluid, and clean/wipe the case (the drained fluid will keep it from dripping further while you are working).
let dry for a bit, make sure it's fully cleaned/dry, and spread some RTV over the joint area, on the bottom and up the sides a bit. I have used blue silicone with good results.
re-fill case. it's a band-aid, but mine lasted 2+ yrs leak free until I got around to pulling it apart and fixing it the right way (sealing the case during a rebuild)
the axle seals on the diff are fairly easy to do, clean everything around the seal/case, remove the inner CV, replace seal
let dry for a bit, make sure it's fully cleaned/dry, and spread some RTV over the joint area, on the bottom and up the sides a bit. I have used blue silicone with good results.
re-fill case. it's a band-aid, but mine lasted 2+ yrs leak free until I got around to pulling it apart and fixing it the right way (sealing the case during a rebuild)
the axle seals on the diff are fairly easy to do, clean everything around the seal/case, remove the inner CV, replace seal