It depends on where the leak is. However, if it is leaking at the pan you need to replace the oil pan gasket and if you are going to do all that work it really isn't all that more to go and change the rear main seal on the back of the engine (and vice a versa). Warning this is a very labor intensive job compaired to the price of the parts. Also, having use of a lift and transmission jack make this job much easier. There is no way I would have done it without these items. It would be a knuckle buster trying to break these bolts loose while lying on your back with only a foot or two of clearance. Also, if you do this plan on a whole weekend job unless you are part of a NASCAR Pit Crew...and if you were you wouldn't have asked ...
That depends on where the oil leak is, is it in the motor self or is one of the seals leaking?
rear main seal
It can leak oil out from the rear of the intake manifold gasket. The oil sending unit is right behind the distributor and it can leak oil too. There is also a gasket that fits on the bottom of the distributor where it goes into the intake that can leak. And the worse thing it could be is the rear main gasket leaking oil and you would have to remove the transmission to repair that.
it is located at the rear of engine block by the distributer.
On the left side near the rear of the engine.
The oil pressure on 91 Silverado 350 is at the rear of the engine on the driver's side, This unit is usually found above the oil filter.Ê
cracked block, or blown head gasket
An oil leak can be from many different places. They include the valve cover, oil pan, front and rear main seals, and oil pressure sending unit.
It's at the top rear of engine, near the Distributor.
Top rear of engine, close to the distributor.
its a rear main oil seal that has to be replaced. mine leaks too
May be your rear seals, need tightened or replaced.