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rear diff leak

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just put boss on lift to try new rims,rear diff is wet on lower part of cover no oil on top. 700 miles if i remove should there be a gasket there. Checked oil level and it is fine


I saw that on mine. Not sure why. Its a black silicone seal. No gasket.
It's most likely the diff venting. You can buy a catch can for it and there are a couple of threads on the Bobs product in this forum.
the leak is from bottom of cover really dont want to go back to dealer, thinking just remove and reseal it. best sealer and diff fluid?
The very first time I hit some pretty high speeds in my Boss (140+), I noticed the diff leaking, too. Well, I thought it was leaking because I only seemed to find fluid on the bottom but the more I looked with my flashlight I saw that it was coming from the breather up top. There is actually a Ford part that you can install and it looks like a tiny turkey baster and it screws right in.

Here is some more info:

Before you take apart your rear end, I would want to be 100% certain that it wasn't the breather. Have you recently hit some high speeds?
06mach1 said:
Should I assume that you tried to tighten the cover bolts? I have seem them loose.

Correct, I think they are 24 lb ft. I find I have to re-torque them after an oil change and some runs at the track. I have also been told to use lock-tight from the racers.
all bolts were snug looked all over rear end see nothing wet at all.have not driven car in 2mo. It on lift because here in ct. when they see a snow flake its time to coat the roads with salt.

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