Transmission Fluid Leak (with pictures)
09-20-2011, 12:50 AM
#21
Racer
Member Since: Jul 2010
Location: NC
Posts: 278
Likes: 0
Received 0 Likes
on
0 Posts
I did the RTV fix and it slowed the leak slightly, but did not stop it. Mine is a pretty bad leak though, so it will need to be fixed whenever I have the motivation to take the back end out.
10-01-2011, 08:25 PM
#22
Pro
Thread Starter
Finally applied some Permatex Ultra Black RTV to the seam between the Tranny and Diff and let it dry for two days with no leaks yet.
Here is a picture - It looks ugly, but if it stops the leak, I'm happy
Here is a picture - It looks ugly, but if it stops the leak, I'm happy
10-09-2011, 07:01 AM
#24
Pro
Thread Starter
Mine was actually leaking from the side, not the bottom (that is why I applied the RTV so far up the side)
Have driven the car about 9 times since applying the RTV and so far, NO leaks
$1,600 (dealership quote) vs. $10.00 in materials and 2 hours of time- No brainer
Have driven the car about 9 times since applying the RTV and so far, NO leaks
$1,600 (dealership quote) vs. $10.00 in materials and 2 hours of time- No brainer
10-09-2011, 11:16 AM
#25
Race Director
10-09-2011, 09:58 PM
#27
Racer
Member Since: Jul 2010
Location: NC
Posts: 278
Likes: 0
Received 0 Likes
on
0 Posts
How is the situation any different from having the gasket material done the right way? I've never heard any negatives from using RTV. The only problem I can see with his use is it not working.
10-09-2011, 10:23 PM
#28
Resident moron
Dope
11-07-2011, 10:48 AM
#29
Le Mans Master
I recently started having the same trans leak problem..... looks like I'll be doing the RTV silicone fix for now. 
And thanks for info guys. I considered fix this fix but wasn't sure if it would work. Now all I need is to buy some more trans fluid.
And thanks for info guys. I considered fix this fix but wasn't sure if it would work. Now all I need is to buy some more trans fluid.
07-17-2014, 05:46 PM
#30
Racer
I know this thread is almost 3 years old, but...the seam that csc67 is referring to is not between the "Tranny and Diff" but between the transmission and tail shaft case. The other end of the tail shaft case, which can't be seen because it is obscured by the rear cradle, does connect to the differential.
07-17-2014, 06:39 PM
#32
Racer
03-29-2017, 07:11 PM
#33
The 2 shaft 0 rings and large case outer O ring are in back of trans tailshaft housing where it bolts to the diff. This is not the same place that is leaking that the OP of this thread posted a picture of. They are 2 different areas prone to leakage. The OP's picture above is where the trans tail housing mates to the main trans case. There is no gasket there and it leaks eventually on most cars. The case can sometimes be pulled apart just enough and rtv put in between halves to fix the leak. Some people get it sealed again without pulling halves completely apart but be careful as to not pull it too far apart unless its standing vertical on end. I knew a guy that was gonna just pull it slightly apart while still in cradle but dont know if he ever did that successfully or not.
Here is a link showing closeup pics where the tailshaft O rings are that your mechanic is talking about. There is usually a hole in bottom of most tailshaft housings that weep fluid when one of the O rings is leaking. It will either leak trans fluid or diff oil depending which O ring is leaking.http://forums.corvetteforum.com/c5-t...-rear-end.html
Here is a excellent link to rebuild pics and you can see exactly what goes where with O rings and case halves. The first pic shows you the case front half that uses no gasket to mate to the tailshaft housing, then the tail housing to the right with O rings shown.http://forums.corvetteforum.com/nort...-smoother.html
Here is a link showing closeup pics where the tailshaft O rings are that your mechanic is talking about. There is usually a hole in bottom of most tailshaft housings that weep fluid when one of the O rings is leaking. It will either leak trans fluid or diff oil depending which O ring is leaking.http://forums.corvetteforum.com/c5-t...-rear-end.html
Here is a excellent link to rebuild pics and you can see exactly what goes where with O rings and case halves. The first pic shows you the case front half that uses no gasket to mate to the tailshaft housing, then the tail housing to the right with O rings shown.http://forums.corvetteforum.com/nort...-smoother.html
04-06-2017, 10:29 PM
#34
04-11-2017, 08:54 PM
#35
Pro
I have a leak on my trans too. It was built by LMR. I sent it back to them to search for a leak and they said they couldn't find one, and that it my be the vent hose. Well is almost been a year now. Its still leaking. I may just get under there and RTV it since it has been working for others. Or should I send it back to LMR and have them do it? Its still under warranty so I wouldn't be charged.
04-07-2018, 07:38 PM
#36
My transmission still leaks when I put it in reverse
it doesn’t leak until I start it and put it in reverse and back out of garage than stops this leak is driving me crazy it does it more on cold days and when it sits for long time what can it be
04-08-2018, 08:48 PM
#37
Advanced
drop the cradle, remove the diff(leaving the trans in the car), un-bolt the extension housing, replace both seals(diff and tranny seal) and re-seal the extension housing. DO NOT USE 3M DISCS TO CLEAN THE SURFACE or you will remove the cross hatch that is machined into the cases/covers. This cross hatch is what holds the sealer onto the case/covers.
06-19-2021, 10:37 AM
#38
Old post, but good to hear.
Didn't know the Black High Temp RTV was available back then. Will give it a try. Dealer wanted $3000 to
replace old RTV seal correctly. A repair should be done with both RTV and a Felpro gasket..
Didn't know the Black High Temp RTV was available back then. Will give it a try. Dealer wanted $3000 to
replace old RTV seal correctly. A repair should be done with both RTV and a Felpro gasket..
10-12-2021, 10:53 AM
#40
7th Gear
Team,
Had the same issue with my 2000 C5.
At first I thought is was a cracked case- as seen in the photo the die cast parting line runs from the passenger side near bolt is very large and runs up under the drain plug. So did a little polishing and confirmed no crack.
Instead of pulling everything apart I did the following.
Drained all ATF fluid- cleaned the whole case/joint with brake cleaner.
Used a powder- baby to be exact- and added 1 quart of ATF- let sit for 4 to 5 hours.
No leak-powder still white- added a 2nd quart. Same process- at 3.5-4 quarts of ATF- powder turned red on passenger side of the joint.
I mark a couple of lines on the joint- 3/8" above and below the leak.
Using a pencil grinder I cut a 1/32 deep- 1/8" wide groove on the seam- mixed up so JB Weld and applied to the groove.
200 miles later no leak!
Thin layer of JB weld is easily removed if Trans needs to be removed or separated.
Hope it helps others.
Had the same issue with my 2000 C5.
At first I thought is was a cracked case- as seen in the photo the die cast parting line runs from the passenger side near bolt is very large and runs up under the drain plug. So did a little polishing and confirmed no crack.
Instead of pulling everything apart I did the following.
Drained all ATF fluid- cleaned the whole case/joint with brake cleaner.
Used a powder- baby to be exact- and added 1 quart of ATF- let sit for 4 to 5 hours.
No leak-powder still white- added a 2nd quart. Same process- at 3.5-4 quarts of ATF- powder turned red on passenger side of the joint.
I mark a couple of lines on the joint- 3/8" above and below the leak.
Using a pencil grinder I cut a 1/32 deep- 1/8" wide groove on the seam- mixed up so JB Weld and applied to the groove.
200 miles later no leak!
Thin layer of JB weld is easily removed if Trans needs to be removed or separated.
Hope it helps others.