I have a 383 LT1 with a Canton Oil Pan (242T). I have changed the gasket twice and it is till leaking oil. The gasket is a Felpro and I put RTV on the ends where the gasket meets the block, not where the gasket meets the pan. I can't seem to get rid of the leak. Looks like it is coming from between the gasket and pan not the gasket and block ( where it has RTV) but not sure. Should I get a different oil pan? Could it be front or rear crank seal, how can I tell?

 

Did you check crankcase vacuum level? Today most cars leak due to bad PCV systems.

 

I don't have a vacuum tester but the pcv is all in tact.

 

But does it work? If it allows air in both directions the crankcase will not have the required vacuum level.

 

How would one test this? Will start search now.