Rear End Leak
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Rear End Leak
...i guess it never ends...
anyway, I was getting my car ready for the new exhaust, and I noticed the rear end is leaking. Right at the where the exhaust pipes split apart.
I've got an '85 with the Auto 3.07, Dana 36. Until I gather the effort to fix this problem, I'd like to just top off the fluid to make sure it doesn't run low. What should I use, where do I fill it at, and is there a dipstick or how do I tell when it's full?
Sorry if these seem like obvious questions, but I've never messed with a rear end of any car before
anyway, I was getting my car ready for the new exhaust, and I noticed the rear end is leaking. Right at the where the exhaust pipes split apart.
I've got an '85 with the Auto 3.07, Dana 36. Until I gather the effort to fix this problem, I'd like to just top off the fluid to make sure it doesn't run low. What should I use, where do I fill it at, and is there a dipstick or how do I tell when it's full?
Sorry if these seem like obvious questions, but I've never messed with a rear end of any car before
Racer
Joined: Jun 2001
Posts: 377
Likes: 10
From: Chicago IL
you'll need a huge allen wrench (not sure of the exact size) and some 90w gear oil (the stinky stuff, wear gloves) - I use an old fashioned oiler that lets me squirt it in horizontally. There is also a gm posi additive that you need to add if you change all of the gear lube. You only need to add as much as it takes to get level with the fill hole. My guess is that you won't need to add much. good luck
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Originally Posted by viii
you'll need a huge allen wrench (not sure of the exact size) and some 90w gear oil (the stinky stuff, wear gloves) - I use an old fashioned oiler that lets me squirt it in horizontally. There is also a gm posi additive that you need to add if you change all of the gear lube. You only need to add as much as it takes to get level with the fill hole. My guess is that you won't need to add much. good luck
I wasn't sure about how full to make it.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Do you use synthetic by chance?
Early on I put Mobil syn in there, which worsened the leak, and upon pullling it recently, saw that parts of it had NO gasket(RTV). The mobil1 had completely washed it away apparently.
Early on I put Mobil syn in there, which worsened the leak, and upon pullling it recently, saw that parts of it had NO gasket(RTV). The mobil1 had completely washed it away apparently.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
These rears dont use a paper gasket.Im betting the RTV in there is getting old.I pulled the rear end out myself and took off the cover and cleaned everything and used the right stuff gasket sealer to reassemble and it did a great job.
If you have a small leak,then you should be ok for a while.If it drips bad at times,you may want to fix the leak.Also be sure the front yoke seal isnt leaking since it can run down to the bottom and appear as if the rear cover is leaking.
If you have a small leak,then you should be ok for a while.If it drips bad at times,you may want to fix the leak.Also be sure the front yoke seal isnt leaking since it can run down to the bottom and appear as if the rear cover is leaking.
Thread Starter
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Originally Posted by Bill's86Coupe
These rears dont use a paper gasket.Im betting the RTV in there is getting old.I pulled the rear end out myself and took off the cover and cleaned everything and used the right stuff gasket sealer to reassemble and it did a great job.
If you have a small leak,then you should be ok for a while.If it drips bad at times,you may want to fix the leak.Also be sure the front yoke seal isnt leaking since it can run down to the bottom and appear as if the rear cover is leaking.
If you have a small leak,then you should be ok for a while.If it drips bad at times,you may want to fix the leak.Also be sure the front yoke seal isnt leaking since it can run down to the bottom and appear as if the rear cover is leaking.
Anyway- thanks for the tips guys
. I picked up Mobil 1 75-90... hopefully it wont make my leak worse.
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Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
Originally Posted by CentralCoaster
Do you use synthetic by chance?
Early on I put Mobil syn in there, which worsened the leak, and upon pullling it recently, saw that parts of it had NO gasket(RTV). The mobil1 had completely washed it away apparently.
Early on I put Mobil syn in there, which worsened the leak, and upon pullling it recently, saw that parts of it had NO gasket(RTV). The mobil1 had completely washed it away apparently.
After putting a newly rebuilt Dana 44 in my '92 A4, I put Mobile 1 synthetic in it. It was sealed correctly with RTV.
In about 5K miles, it was leaking -- a lot of the RTV was disolved.
Took it apart and re-sealed it and put regular gear oil in it and have never had a problem since.
Here is one you are going to have a hard time believing, but it is true:
I also have a '64 Corvette coupe with a Muncie four speed that doesn't get driven much.
Several years ago, I put Mobile 1 gear oil in it. After about two years, I crawled under it and saw something very unusual -- the case of the transmission was glistening all over up to the fill plug. It looked like someone had taken the transmission and lowered it in transmission fluid up to the fill plug.
The Mobile 1 gear oil leaked right through the porous aluminum case. It took two years to leak through.
I switched back to regular gear oil, but it will probably take two years for the stuff that is already coming through.
I also found out that the respected Muncie transmission rebuilders recommend that you do NOT put synthetic gear oil in their transmissions.
Tom Piper
Last edited by Tom Piper; Aug 16, 2005 at 07:05 PM.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I stuck mobil in mine after opening it because that's all I had. Used the right stuff on the case.
Only the best for my baby.
Cross your fingers.
Only the best for my baby.
Cross your fingers.
