when the engine is started, after about 10 seconds i can hear a whining nosie comming from my oil pan. right now i'm in the process of dropping the the oil pan to see whats up. are there any opinions of what i might fine or what to look for to help me solve this problem.

 

Wha is the oil pressure?

Is the sound a constant whine, or a cyclical, impulsive screetching noise?

 

the noise might be a cyclical screetching sound ? today i pull the oil pan off and what i found was the coating wore off some of mains and rod bearing. i have put two different rebuilded l98's in this car and i am having the same problem. all needed crankshafts
do these engine take tight are lose clearances. one thing i fail to replace was the engine oil cooler. could the oil cooler be contaminated. my oil pressure was 60 psi at start up and 40 psi when warmed up.

 

Considering its the second engine with the same problem its probably the oil cooler. If its restiricted, the extra load on the oil pump could make a sound similar to the one you describe.

 

Not to mention the oil starcation eating bearings and piston skirts.