Rear Main Seal Leak Ford 302 AOD Transmission

Question

I have an 88 Ford 302 and I'm fairly sure that the rear main seal is leaking. I'm hesitant about using 10W-50 since the engine only has 80k on it. I'm also hesitant about using some of that "oil stop leak" stuff since I've heard only bad things about how it makes gaskets swell and deteriorate quickly.

Does anyone have any ideas other than replacing it (a $500 job...)? Should I not be worried about the 10W-50 and use it anyway?

Answer 1

I regularly use Berryman's Chemtool B-12 on various vehicles to stop seal leaks and clean out the engine (rings, lifters, sludge, etc.). It does soften hardened seals which allows them to again seal. The cleaning action around the rings also stops or reduces oil burning. Just before an oil change, add the Chemtool to a warmed up engine SLOWLY. Replace the oil filler cap and fast idle the engine (1,500 rpm) for 30 minutes. Shut off and drain the oil, replace the filter and use 10-40 or 20-50 oil; 5-30 is too thin to protect properly except on brand new engines with less than 60,000 miles. The oils on the market targeting high mileage vehicles has the same active ingredient (M.E.K.) but it is in the crankcase continually instead of for a brief period. The Berryman's flush is superior. I have also used it in power steering pumps (small amount, leave it in). Do not use on engines that have thew old rope rear main seals. It takes the wax off the rope and they leak worse than before (1985 Buick V-6)

Answer 2

You need the seal replaced. Your going to end up stranded on a bridge or highway.

Answer 3

you can use the 10-50 but it won't help much a new seal is the only way to stop the leak. and don't waste you bucks on bogus stop leak c**p,,,

Answer 4

Be sure your PCV valve is good, and the vacuum to it is good as well. If the PCV doesn't work properly, the crankcase gasses will look for a way the vent. They will sometimes do that via shaft seals.

Change the PCV valve, and check the hose and inlet for partial blockage.