Mysterious oil leak

I have a 1975 Ford F150 with a 390. I’ve noticed that the last few days i have an oil leak that just seems to be getting bigger and bigger. I looked under the truck and I noticed that the whole back of my engine’s oil pan is covered with oil and that is where i think its dripping onto the ground at. When the engines hot it just drips onto the ground like crazy.

What do you think could be leaking?

Check if the oil pressure sending unit is leaking. It’s screwed into the side of the engine, next to the oil filter.


Nice one to check, Tester. We just love plastic parts. Had that problem on a Chevy 350.

If it is the BACK of the engine, near center, like where the engine and transmission mount together, then I suspect rear main seal. And at this rate, it could be almost a total blowout.

Well I just got done checking over this and it was nice and tight.

Don’t check for tightness. Start the engine and see if the sending unit is leaking.


I checked the sending unit and it did’nt appear to be leaking. The sending unit also isnt real old either.