So lately I have noticed a smell of burning oil after parking the car in the garage. Nothing crazy but was still there after each drive. I recently replaced all of the coolant hoses and valve cover gaskets last year, as I was having leaks and a burning smell at that time. I looked all around the engine bay and saw nothing....but when I looked at the rear, I saw my problem.

The differential has several spots that are covered in oil. However the main areas with oil are parts of the exhaust and near the driveshaft.

I should note that the car drives and shifts smoothly. There is no noise from the rear end at all.













I went ahead and pulled the breather out and thought it was clogged but it really didn't look that bad. Cleaned it anyway and reinstalled it.








And cleaned:



Any thoughts? I may just drive it a bit after cleaning the breather and see if there are any new spots?

 

Yes, that’s what I would do - drive it and see if you fixed the problem. I had a small differential leak several years ago and I replaced the breather. No drips since then. If I remember right, I think I actually replaced it instead of cleaning it but I don’t remember why.

 

Pianoman90, that’s definitely a good start with the cleaning of the breather. Your next step is to top off the differential oil level. Fortunately for you, you have a LWB jag so it’ll be easier to get that fill plug out. After topping it off and using brake cleaner on all the diff leaks, if you have a compressor, blow it off dry so you can keep an eye on it for any further leaks.

Don’t be disappointed if you see it leaking from there again. It’s a very common area to leak. The diff oil travels up through the splines of the pinion and comes out from the pinion nut on the front. The problem is that the pinion shaft metallurgy is softer than the pinion snub that bolts to the front of it. The splines get shifted over and worn out and slop within those splines ensue. Replacing the expensive snub will do very little for your leak unless the pinion seal is damaged. I have several times successfully and “carefully” removed the pinion snub, carefully cleaned off the pinion splines with Q-Tips and brake cleaner on them, dried off all the splines on the snub and pinion, applied a ring of rtv around the front of the pinion shaft and slid the snub over it. The idea was to have the rtv slide down the pinion shaft while reinstalling the snub back on. Letting it sit overnight at least without moving would be beneficial to let it cure. You don’t need to remove the exhaust but you obviously need to completely remove the flex coupler on the front of the differential and set the driveshaft off to the side and secure it so it’s out of your way to work on the pinion.