I got a used oil pan from a guy I work with but he did not know what year it came from. So is there a way to tell if it needs a thick gasket. I heard it depends on the pan. I have an 80 z28 with a 350.
Thanks

Bolt it up fingr tight and look at the gap between the timing cover and pan. If it is fairly even all across and narrow, it is the smaller front gasket. If it has a bigger gap in the center, it is the thicker gasket. Either way, get a Felpro one piece reusable rubber gasket, you will be glad that you did.

Jon