kflohrit

So I picked up my '98 M6 about a month ago and have been fixing little things here and there. I bought the car for a hobby and knew with 113k miles there would be issues. The rear end has a decent leak and I was hoping it was only the axle seals, but after being under it for the exhaust install, I see it's much worse. I took it into a local independent shop and they called me today to say they want to replace all the seals in it. They quoted $1300 since they need to drop it down to get a good look at the front seal and replace it as well. I had a little sticker shock after seeing what the axle seals require, but can't find much information on the front seal and what all is involved. I told them to go ahead with the repairs because I'm trusting they are not hosing me. Anyone else had any experience with it?

SaberD

I highly doubt it's the front seal. I'd say there is about a 0.001% chance that it is the front or rear seal.

it's most likely what the vetters here call "leaky butt" syndrome. There is a TSB for this where the side covers need to be removed, cleaned, new O-rings, and a special GM anaerobic sealant must be used. Once the side covers are off, putting in new axle seals is literally a 1 minute job, so if they are charging you labor time for replacing the axle seals they are screwing you.

You don't need to remove the drivetrain to replace the side covers. you may want to drop the rear cradle slightly for better access, but that's it.

All in all this should be about a 2-3 hour job with about $150 max in parts/fluids.

kflohrit

I went to the shop and talked to the mechanic and walked around under the car. The front seal (little rubber o-ring that goes around the large diameter) was leaking, as well as the rear and middle section of the transmission. Fortunately, he was correct and it will be leak free when all is said and done. Additionally, I'm having them replace the clutch release assembly since it was making some noise and has 114k miles on it. All in all, I'm very happy with the experience. The guy worked at Chevrolet as a master mechanic before working at this shop and is familiar with these cars. After spending about a half hour with him discussing the car, I am very confident in his decisions and ability. He also was being very careful with the Corsa exhaust I just installed and wheels, which also means a lot.

Thank you for the response though. I also got to check out the clutch and pressure plate while I was under it and can check those things off my "concerns" list.

Overall, the seller I bought the car from was upfront with me and honest. It's nice to know there are still honest people out there.