Just out of curiosity... I had my rear main oil seal replaced by a local diesel shop while I had my engine out last winter. I was told that it was a must! to use the correct tool to seat that properly, or it would leak. Took the engine up and paid $400 plus materials to have it done. Not 100% sure yet, but suspect it is leaking, and if I have to redo it, would like to do it myself, without the tool. Has anyone else done this themselves, and was it successful long term? I'm going to replace my turbo o rings first, but just curious...

 

i would look in the valley for a leak first. the drain hole up there allows it to drain down the back side and look like a rear main problem when its not.

 

Are you sure it is the main seal? Is there oil on top of the motor in the valley? It is usually very unlikely that the rear main seal will develop a leak. Not sure that you had one originally either. It just isn't a very common issue. Now leaks on top of the motor are common and mimic a leaking rear seal. I would definitely clean the top of the motor and see if there is oil collecting up there.

 

Make sure you know where the actual leak is before doing any additional repairs. Most people in the know here will tell you that the rear main seal is a rare problem, and is usually a leak from somewhere else up above.
Jim.

 

Ditto what Chris said. I would check the turbo o rings first.

 

Man, I don't type fast enough.

 

Hey Jetdoc, That Samuel Adams quote is right on. Amazing the insite of our founding fathers. To think we have a supreme court justice who doesn't think the U.S. constitution is a good example for an emerging nation to use. We are in trouble!

 

Dont worry Jim.... I dont type that fast either but nobody mentioned that the oil could be coming from the engine valley above... Usually from a turbo leak or an HPOP leak. I can't believe they missed that one.

 

maybe some one should take a second look. ..................

 

Maybe I should of put an

*Insert sarcasm here* before my post.

I meant that as a joke since it is a rare thing that these engines develop a rear main leak and it usually is leaking from the top valley. I did see the other posts.

 

Because like me, while hunting and pecking there were 3 more posts before he finished.

 

See, It happened again! Damn, I give up.

 

Well, I was planning on doing my turbo o rings first to be on the safe side. I do feel better knowing that the seal is less common. I had it done the first time because the engine was out, I was doing the clutch, oil pan etc, so I just figured I'd have it done and over with all at once. I didn't replace my turbo o rings at the time, just used my old ones, so that's most likely my problem. Thanks for the assurance. I'm still curious about doing it by yourself though. When I had it done, I saw the 'special tool' and it was just a flat price of steel with holes cut that would line up with flywheel bolts so that the seal could be pulled on uniformly. Almost looked like something that could be made at home. Has anyone done this? I've done rear mains on gasses, but heard its a lot more precise with diesels for some reason?

 

i was just tuggin at your chain anyway. i'm in one of those playful moods today.

 

Pretty rare a main leaks. I replaced the one on our 94.5 at 300K+ miles whole I had the clutch and all out. The seal i got for this truck came with the tool, a plastic driver that drives the seal and crank ring (new bearing surface to ride on) all at one time.

It is good to have a tool to drive the seal evenly and seat it flush. But it can be done without it just fine, slowly and evenly tap the seal with a hammer around and around and around till the face of the seal is flush with the block all the way around. If your seal comes with a new crank ring it should come with a tool.