If you overfill the oil level in a stock sbc pan by 1/2 quart will that bring the level high enough to leak out the gasket in the back of the oil pan? I overfilled my oil by 1/4 to 1/2 of a quart. I then drove the truck that I tow my boat with for about ten miles and then parked it for a week. when I came back there was a large puddle of oil that had leaked out from the back of the pan or the rear main seal. I think it leaked out when the truck was parked. I have always thought that it was my rear main seal that was leaking and i was putting it off until I could overhaul the engine. Do you think it is worth while to replace the pan gasket to see if that might be my leak. It is very difficult to be sure exactly what is leaking. Has anyone ever poured oil into a pan to see how high the level is inside?

Thanks

I've never had that happen if it's just 1/4 to 1/2 a quart over.
Was the truck parked facing uphill? You know that'll put the oil against the rear pan gasket.
Are you sure it isn't a valve cover leaking? If it leaks at the rear corner it'll run down and look like a seal or pan gasket leak.
If it's leaking from the rear seal it'll usually be dripping from the bell housing. A pan gasket, and sometimes a valve cover, will drip from the bottom of the pan.
Best bet is to thoroughly clean the engine and run it for a short while and then look carefully for the leak.

Iggy,

It was parked on flat ground and it is leaking from the cover on the bell housing. I guess I was just hoping that a pan gasket might help me out.

Thanks