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Stinky oil leak: Worth fixing?

So my rear main engine seal is leaking oil: not a tremendous amount, but enough that when it burns up on the engine it stinks to high heaven. Seriously, I can find my car in a parking lot by scent. Everyone I’ve talked to about fixing it says that the repair is so costly as to not be worth doing, and suggest an air freshener. I do not find this answer very helpful.

What do you guys think? Are there any long-term health risks associated with exposure to these kind of fumes? What should I realistically expect to pay for this repair?

My Nissan had a main engine seal leak up front. It was fixed for $600 or so. Yours might cost more.

The transmission has to come out to replace the rear main seal.

It’s not healthy to breathe any smoke from burning petroleum products.

You might want to switch the oil over to a high mileage oil. Such as Valvoline Max Life. These oils have additives that cause the engine seals to swell slightly, thereby slowing down/stopping seal leaks.


Are You Sure It’s The Rear Main Seal That’s Leaking?

Are you sure that’s the only leak, the “stinky” leak?

It might be easier to fashion an exhaust pipe shield. What year is this vehicle?


It’s a '98. There were a number of other leaks, but they’ve all been repaired.

I Would Guess The Oil Drips From The Lowest Point Of The Engine/Transmission.

What’s Under There That Burns It?


Huh. I’m not sure – I guess I figured it must be burning up on the engine, somewhere? I’m kind of dumb about this sort of thing.

The exhaust pipe runs right at the seam between the transmission and engine.


Tester, Thanks. I’m Not A Honda Guy, Obviously.

What about fabricating an oil shield? Is there room or anything to attach to down there?


I’m not sure. How would I fashion such a thing?

Naw. The pipe hanger is attached to the bell housing of the transmission. So the pipe is really close for any clearance for a heat shield.

The leak has to to stopped somehow. Be it with the replacement of the seal, or an additive that stops the leaks.


I’d give the high mileage oil a shot first. It’s a whole heck of a lot cheaper than pulling the transmission to replace the seal. Do the next couple of oil changes with it and see what happens. You may get lucky.

I should have mentioned this before, but I’ve definitely tried high mileage oil, in addition to those additives that claim to be able to fix leaks. No luck.

This has been going on for around a year.

Then I’m going to ask, have you checked/replaced the PCV valve?

If this isn’t functioning correctly, it can allow excess crankcase pressure to build in the engine pushing oil past the seal.


I’ll look into that. If I have to bite the bullet and have the seal replaced, what should I expect to pay? At what point will I know if I’m being ripped off?