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Engine Oil Leak

Mr.PetesMustang

New Member
Hey guys. I need a little help with an engine oil leak. I have a 1986 Mustang GT 5.0 5-SP MT that I bought brand new in '86 and is completely stock and mostly original. It has 60K original miles, mostly from the first six years. The last 29 years the car has been garaged and driven for fun on an occasional weekend and to smog stations every two years. I have had an engine oil leak for years now (don't remember how long) that seems to be coming from the rear of the engine kinda in the middle. It leaks with the engine off and is a VERY slow drip on the drip pan on the garage floor under the car. I don't know if it leaks when running (I will assume it does). The car runs great, clutch is fine. I cannot remember if the oil level in the oil pan is below the oil pan gasket and rear main seal. If it is, and the engine is off, where could the leak be coming from? Before I get in there and pull the trans or oil pan I would like to know if that makes sense or if I'm wasting my time and energy when it could possibly be something else.

Any help or advice would be appreciated. Thanks!!!!
 
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tycosp23

New Member
I would thinks its your pan or rear main seal. What happens to seals when vehicles are not run a lot they dry out and the next time you start it they wear. Repeat this cycle over and over again and that's how leaks start. I would look into those problems.
 

Blueknights75

Active Member
Suggest just replacing valve cover gaskets, oil pan gasket, and low oil sensor gasket (if equipped). Get rid of that cork and get some Fel Pro one piece gaskets especially for the oil pan. After I changed all of mine I then got 5 cans of brake cleaner and cleaned up everything. Now I know that my main rear is leaking just a little bit but I will wait until the clutch replacement to change that out.
 

Mr.PetesMustang

New Member
Suggest just replacing valve cover gaskets, oil pan gasket, and low oil sensor gasket (if equipped). Get rid of that cork and get some Fel Pro one piece gaskets especially for the oil pan. After I changed all of mine I then got 5 cans of brake cleaner and cleaned up everything. Now I know that my main rear is leaking just a little bit but I will wait until the clutch replacement to change that out.
Thank you for your ideas. I did do the valve cover gaskets a few years ago so I am pretty sure it's not that. How do you change the oil pan gasket without dropping the pan??
 

Mr.PetesMustang

New Member
I would thinks its your pan or rear main seal. What happens to seals when vehicles are not run a lot they dry out and the next time you start it they wear. Repeat this cycle over and over again and that's how leaks start. I would look into those problems.
Is the rear main and oil pan gasket above or below the oil level line? Since it leaks when the engine is off it has to be someting that is below the oil level line.
 

Blueknights75

Active Member
also recommend replacing the oil drain pan bolts and gaskets. Mine were leaking pretty good due to previous owner not having a washer or gasket on either drain plugs.
 
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