[BPN]

Hi all!

I've had the pleasure recently of driving my Camaro on the German "Autobahn", known for its non-existant speed limit. As such, I went ahead and tested out this car's high speed behaviour (130 MPH and up). When I got back home and got under the car a few days later for something else, I noticed that the left side of the differential was wet with oil. It seemed to come from the left axle shaft seal.

I took out some brake cleaner and a rag and cleaned it all up. Then I drove it for some longer distances several times at more moderate speeds (let's say up to 60 MPH with some peaks up to 90 MPH in short sprints at traffic lights ) and never saw another bit of leakage. I even checked the fluid level using the check and fill plug - the level was fine. Must have been a small leak.

A while later, I had the good fortune to take the car drag racing at an American car event. That was my first time racing, so it was pretty awesome. At the end of the quarter mile speeds in excess of 130 MPH were again reached and afterwards - you guessed it- more leakage from the left side of the differential at the left axle shaft seal. After cleaning it up, checking the fluid level (still fine) and driving it normally again for a while, no more leaks up to this point.

I found out these diffs have a breather tube and suspected this leakage might come from a clog in this tube somewhere. I removed the tube from the top of the diff and checked it, but it's not clogged, folded or anything of the sort. I also noticed there is no one-way valve/check valve inside the rubber boot that connects to the diff. Is said valve inside the diff, or is it not there at all? If it's there, could it be jammed somehow, causing this leak?

Summarizing, as long as I drive the Camaro at moderate speeds (even if I floor it accelerating there), no leakage occurs. But when the speeds get higher, the leakage returns. To me, that indicated that the seal itself isn't bad, since I'd expect that to cause leaks at all speeds in greater or lesser form. What could be the cause?

I'm kind of reluctant to drive the car at higher speeds now, afraid to wreck something in the rear end...