Grrr. I got the Bonne inspected today. I've had my "self-changing oil" option since shortly after I bought the car, but it'* been getting worse. I was hoping it was a pan gasket but the place where I got it inspected said it looks like the LIM is leaking as well as the rear main seal. Everybody'* had some exposure to the LIM leak, even if it'* pics on here. I haven't heard of a rear main seal leaking on one of our 3.8'*. Is it common or am I just lucky?


Maybe it'* time to go shopping?

The rear seal leak is not all that uncommon. Most times, it is quite minor and if so, many just leave it alone. I believe that the engine has to be pulled to replace that seal. The LIM oil leak could be a "splash type" leak from the end seals on the lifter valley. If you keep the car, the LIM/UIM gaskets should be replaced.

They said the rear main was really wet. I'd like to get away with just UIM and LIM seals. The leak has really gotten bad...

It does sound as if the rear seal will have to be replaced. Let'* see....I think the next NEBF is in May!

I'm not much for "mechanic in a can" products, but if it'* really bad, I think I'd try one of those seal-swelling products just for giggles.

I can't remember anyone here complaining about a rear main seal leak. Mine is dry at 147K, so....gotta be rare.

But the traditional Pontiac V-8? Well, that'* a different story.

I thought about some of that stop leak stuff. I'd like to hear from someone who'* used it There are a few different manufacturers....

Go after your LIM first. That should be a non-pressure leak in the corners where the heads, block, and LIM all meet.

Do that first, then we'll come back to the rear main seal afterwards. Most of us have the rear main seal replaced when we do trans service. I did on my 93, and now will on my 95. Neither ever leaked, though. Just good practice.

I wouldn't put the gunk crap in the motor except as a last option for the rear main.

Thanks Will. The car had a GM reman tranny before I bought it but if it wasn't leaking I doubt the previous owner would have replaced it. What'* the ballpark figure for upper and lower gaskets? I'm guessing GM is the way to go.

Has the PCV valve been checked lately?

Replaced it about 6 months ago.