Noticed some oil residue on my exhaust pipes today and crawled around under the truck to get a closer look...

I've read some of the posts here about leaky rear main seals and pan gaskets, so I realize this is a common problem.

The truck only has 66,000 miles on it and for the most part has lived a pretty easy life. At its last oil change, I went with a synthetic blend and am thinking this may be the reason that I'm noticing the leak...

Crawling around underneath, I noticed that the dipstick tube looks like its been replaced...it was sealed with some silicone but doesn't appear to be leaking. Just under the tube, however, the pan gasket has bulged out and I can pretty clearly see a sliver of one of the bolt holes peeking out. Some oil marks on the exhaust pipe indicate a leak of some sort coming from this part of the pan rail.

After cleaning the pan & transmisson bellhousing thoroughly, I took it for a test drive, alternating RPMs between idle and 4,500. When I pulled back in, I noticed a small amount of oil on the lip of the bellhousing, between the engine rear plate and the bellhousing itself. (just forward of the rubber stopper on the bottom center of the bellhousing). It appears that a small amount of oil is leaking thru this passage between the bellhousing and the plate...Actually, it looked like it was coming from the flywheel. 1,000 miles after the oil change, I've noticed no difference in the oil level...still full. I would guess that I'm only dripping a couple of drops per day. Is this something to be concerned about? Can I expect the rear seal/pan gasket to last until my rebuild (planned for 100,000 miles)? Or do I need to drop the tranny and bite the bullet...

Would occasional medium duty towing or agressive driving cause problems?

Suggestions appreciated!

Thanx

 

If you haven't lost any oil in 1000 miles, I wouldn't worry about it.

 

what engine do you have? chances are, you have a 302, or a 300. these engines will run forever and when properly taken care of, they will run forever. or at least more than 166k. dunno what to tell you

 

thanks for the imput guys.

After degreasing the pan & bellhousing and slowly revving it up and down, I noticed that the main seal is not the culprit. My pan gasket is crap I Never thought that would be good news!