Rear Differential Vent Leak
Thread Starter
2nd Gear
Joined: Nov 2009
Posts: 2
Likes: 0
Rear Differential Vent Leak
I'm having a bit of trouble with my stock Getrag 3:42 rear differential on my 98 coupe. I registered yesterday and this is my first thread. I just wanted to see if any of you guys had this problem, and if so, if you found a solution.
Apparently, after extended highway driving, the vent on top leaks fluid. I had my dealership diagnose the problem and they said my transmission and both seals of my rear diff were leaking. Naturally, I was skeptical since the driver's side cover and and both seals on the differential were replaced < 2 years ago when I had the same symptoms (spots on my garage floor). The transmission was also rebuilt < a year ago.
Once I got it on the lift, my transmission guy and I concluded the only place there could be fluid leaking was on top of the differential where the vent is. All the seals looked fine and fluid doesn't run up.
After talking with two rear diff mechanics, I don't have a mechanical problem since there is no unusual noise. They thought I should get on an internet forum to see if : 1-I need a special rear diff fluid 2- I'm at the wrong capacity(maybe a little below the fill hole) 3-I need a special anti-foaming additive.
Any advice or input would be appreciated.
Apparently, after extended highway driving, the vent on top leaks fluid. I had my dealership diagnose the problem and they said my transmission and both seals of my rear diff were leaking. Naturally, I was skeptical since the driver's side cover and and both seals on the differential were replaced < 2 years ago when I had the same symptoms (spots on my garage floor). The transmission was also rebuilt < a year ago.
Once I got it on the lift, my transmission guy and I concluded the only place there could be fluid leaking was on top of the differential where the vent is. All the seals looked fine and fluid doesn't run up.
After talking with two rear diff mechanics, I don't have a mechanical problem since there is no unusual noise. They thought I should get on an internet forum to see if : 1-I need a special rear diff fluid 2- I'm at the wrong capacity(maybe a little below the fill hole) 3-I need a special anti-foaming additive.
Any advice or input would be appreciated.
Safety Car
Joined: Oct 2003
Posts: 3,699
Likes: 16
From: Sun City- Menifee Calif.
Usually when the vent leaks its because its too full. You could try changing the fluid Make sure it has L S on the label & 75/90 Should take 1.7 -1.8 QT. My vent leaked when it was over filled after a long drive in 110 degree temps . Hope this helps you. 
Thread Starter
2nd Gear
Joined: Nov 2009
Posts: 2
Likes: 0
Thanks for the reply Dennis.
I needed the type and capacity fluid, I was planning to change the fluid anyway. The wrong capacity explanation makes the most sense.
This forum is a great resource, I'll reply to a few treads if I have some experience with their particular situation.
Thanks again
I needed the type and capacity fluid, I was planning to change the fluid anyway. The wrong capacity explanation makes the most sense.
This forum is a great resource, I'll reply to a few treads if I have some experience with their particular situation.
Thanks again
