Rear Main Seal Replacement
Thread Starter
Staging Lane
Joined: Oct 2004
Posts: 84
Likes: 0
From: Lawrenceville,GA
Rear Main Seal Replacement I would like to replace my rear main seal while my transmission is out. There is some leakage although it doesn't drip from the bellhousing yet. I have over 90,000 miles on the engine. I've read my GM service manual and it installs the seal with the Kent Moore tool. It says the cover is aligned prior to installing the seal. As I read it you remove the seal and reinstall with the tool. I searched and read previous posts where people are talking about loosening the cover bolts to center the seal. That isn't the GM method though. How are you installing the seal? Has anyone used a seal puller and been sucessfull with taping it in on the edges with a block of wood? Has anyone found a cheap alternative for a seal driver? I'm not sure why if the cover is already aligned you would want to loosen it?
Wheel 2 Wheel makes a GM replacement tool for the real seal. It is billet aluminum - looks pricey. When I pulled my tranny I just used a seal puller (I think that is how I got it out) and then just a block of wood to get in the new one. That is what I have done for the front three times now. When I pulled the engine miles later there was no leakage from the rear seal. The Kent Moore tool just to do the alignment is around $250 then there is the seal installer too.
I guess you could look at it from the stand point of how much will new clutch pads be if it leaks bad and how much is it worth it to you not to have to pull the tranny if the wood doesn't work.
I guess you could look at it from the stand point of how much will new clutch pads be if it leaks bad and how much is it worth it to you not to have to pull the tranny if the wood doesn't work.
Thread Starter
Staging Lane
Joined: Oct 2004
Posts: 84
Likes: 0
From: Lawrenceville,GA
What I want to do is replace it now, because in the next 30,000 or so that I hope the Spec 3 will last, it may leak worse. I have replaced many other seals and some rear main seals with just a block of wood to tap it in. I didn't have any leaks from them. I was confused reading the other posts about loosening the cover. I hoped people had just removed it and tapped it in carefully and had no leaks. It sounds like that worked fine for you. Unless someone tells me there is a reason why this doesn't work, I will go ahead and do it carefully. No I don't want to drop the trans again before I have to. Thanks for the reply!
Ive replaced two. I did it just like I do the front seals except I also try to keep the bottom edge flush for the oil pan to seal against etc. I just had to keep an eye out cause one side or the other would rotate just a little so when I got the seal over the crank I just rotated it to get it flush, then tightened it up. I also used a piece of emery cloth on the other cause he had a small ridge I sanded smoth before the installation of the new seal. Neither or them leaked or leak now. No lube just right out of the package. I used big piece of PVC to install the seal on the cover. It was a chance I took to do it this way and I knew it would work and it did. Good luck on what ever you decide to do.
