I have a rear main seal leaking at 270,000 miles and my question is do thes seals wear and leak or is there a big chance I'm going to find bigger problem when I get in there?

 

The seal started leaking on my 89 at about 120000. I had a fellow up the road that is pretty reliable go in and replace it. It is a double lipped teflon seal and must be installed DRY. He din't believe that but I copied the service manual on seal replacement and took it to him. As best I remember, the seal was about $80 from Cummins. He replaced it and no further problems.

 

You made it 70k farther than my 91 1ton before leaking,I went ahead and done a clutch job on mine when down,it is not a difficult job,if you have a place to do it in out of the weather. As above I could not believe that it went in dry,mine was really tight and somewhat of a booger to get in,but it finally does, Goodluck Rick

 

$80 and labor will pay for a lot of oil. Is it a Real bad leak? Mine drips, but I'm waiting to see how a couple other projects are gonna go so I can tackle it at the same time.

 

If it is possibly leaking from a build up of contaminants and sludge around the seal, I would suggest visiting www.AutoRX.com I am not one to put faith in oil additives, but tried this on a seal leaky gas engine of mine, and it stopped the leak.

It's actually a metal cleaner that uses the engine oil as the carrier, and slowy cleans build up inside the engine. The stuff isn't cheap, but less expensive than replacing the seal. Of course, though, you will not find out if the seal is ripped or torn until you run a cycle of this stuff.

I am NOT afilliated with this company.

 

I guess I'll go ahead and do it myself pulling a tranny isn't to tough on 2wd it should save me some money. I was just wonedring how long the main shaft bearings last. Sometimes a leaking seal is a sign of bearing failure.

 

the m.s. are prone to looking bad but the good news it ez to replace along with everything else while you there
main seal
fork, t.o. bng. and take a good look at your cam and oil gally plugs (they can be a cause for a drible also)

 

On the early Dodges, the outside of the seal was metal, and the seal would actually work loose from the engine, and some would start to fall apart. The new seals now have rubber ribs on the OD and they seem to stay put a lot better.

 

If you still need the seal, I came across one on ebay today.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2449204712

Hurry and you may be able to get it fairly cheap.