Rear main seal

[SSPaul]

Just be sure that the leak is from the rear main before pulling the the trans. These engines are notorious for lower intake gaskets leaking oil. Try and look down the back of the engine with a flashlight and mirror and look to see if there is any signs of leakage from the lower. If you pull the intake don't forget to replace the valve Cover gaskets,pcv valve and the metal pcv valve filter below the valve.