Rear Main Seal Replacement

If you have an oil leak at the rear of the engine and it isn't the dreaded Intake Manifold leak (oily up high at the back of the intake manifold on passenger side) this seal is the likely culprit. If you are doing any work that requires removing the clutch it is a wise idea to replace this seal while you are there. I describe the installation since the pictures are better after all the oil has been cleaned up. Obviously if you follow the directions from last to first that will give the disassembly procedure. Click on any image for an enlarged view.

1.		This first picture shows the rear of the engine with the Transmission, Clutch, and the old Rear Main Seal all removed. The oil pan does not have to be lowered (mine is in this picture since I had lowered it to remove the rear main bearing housing).
2.		This picture shows the new seal installed. I used a GM seal, Part number 1255-4314. This is a newer design that is for a '97 and later LT1 and it is supposed to be better than the original '95 part. The open end of the seal goes in toward the engine. Gently tap evenly around the seal with a hammer and block of wood until you feel that the seal is solidly seated around its entire circumference. Also in this picture I placed a screw driver at one of the three pry points that you use to remove the old seal. Never having done this before I didn't know exactly how the seal should come out. So for anyone else in that same boat, there's the info.

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