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'98 Ford Rear Main Seal Leak & Repair

I have a '98 Ford Escort ZX2 with 83K miles. I live in Santa Monica and drive mainly surface streets - my daily commute is about 10 miles RT. I have a very slow oil leak my mechanic says is the rear main seal. He said I have time to save up the $900 to have this fixed, but should eventually get it done. I’ve read online about a few products like Bar’s Leaks that may help swell the seal and repair it - there’s a lot of different reviews out there, from “it works great” to “made the leak worse”. My brother-in-law says don’t do it -may cause more damage. Anyone have any experience or words of wisdom on these products?

Rear main seals get a lot of blame for leaks that are actually somewhere else. With most oil leaks, the oil drains down the side of the block until it gets to the pan gasket or rear main seal area, there it drips. Most often the leak is higher up and easier and cheaper to fix.

Look for leaks around the oil pressure sending unit, oil filter, valve cover gasket, distributor gasket.

If you’re not leaving puddles under the car when you park, then I would ignore it & just make sure you’re someone who checks the oil regularly. Its a '98. Its going to leak some oil.

If its a manual & if its the rear main (see Keith’s note above) you can get it taken care of whenever you need to replace the clutch.

I wouldn’t do the leak sealers.

$900 is a lot to spen on a very slow oil leak on a 98 car. Replace you pcv and it may stop leaking.

I’m with the other comments. Oil is cheap and it is a very slow leak. You can buy a whole lot of oil for $900, probably enough to outlive the useful life of the vehicle.

“High-Mileage” motor oil contains seal conditioners (softeners) that might solve the problem…

To the practical advice above, let me add; When an old engine can burn 3 tanks full of gasoline before needing a quart of oil added and the repair costs more than $100, keeping it topped off is the best solution. If the car has a manual transmission the seal will be an easy add on repair when the clutch is replaced.

Thanks guys for all the advice - let me just add that they orginally couldn’t find out where the leak was coming from, so they put dye in the oil case and told me to drive it for a week. Brought it back, left it for the day and got the diagnosis. Keith mentioned it might be something else, but I’m hoping they’ve ruled that out by using the dye? FYI, I take the car to Buerge Ford dealership in LA. I’ll pass on the additives for now and see what happens. Interestingly enough, I’ve checked under my car for the past 3 mornings and nothing. It’s an automatic, so no such luck on the easy add on repair. I’ll save the money just in case…
Happy holidays!

A rear main…if its leaking has only one cure…replacement. Its not a terribly difficult job, and I’ve done my fair share…its just that the rear mains take a good long while to go bad to the point of leaking…I hope your diag is on the money.

My Grandfather…rest his soul would tell you to drop a Qt of motor oil and replace it with BRAKE FLUID :slight_smile: lol…he was nutz but I tell you some of his old school tricks really did save the day.

NOW I am NOT telling you to do this, bec as I have gotten older and slightly wiser I know that wherever that brake fluid would flow…whatever seal it touched…would SWELL… It also breaks down the material in the process…so any benefits would be quickly outwieghd by the other seals that you sent to the graveyard…

I miss my Pops…

Yeah, Honda. Not a terribly difficult job if you have the tools and talent to pull a transmission (/sarc). That is the only way to access the rear main seal. I’d use a ‘High-mileage’ oil long before deciding to spend a grand to change out that $16 seal.