trying to diagnose my oil leak at the rear of engine and front of transmission. Think it might be rear main seal but friend says oil pan. Has anyone had this problem?

 

Yeah, and it's almost always been the rear halfmoon seal in the valve cover. They get old and stiff, and leak down onto the transmission, making it SEEM to be leaking. Also, putting them in correctly can be a royal pita, so be very careful.

Just my experience in my 87 2WD pickup.
Pat☺

 

I've been installing these in all the engines I work on. Do recommend. https://22reperformance.com/22re-gas...num-half-moons