Chevrolet
1992 Silverado K1500
4WD
5.7L 350cc
Club cab, short bed-super common truck

So I rebuilt the engine and am still working out the querks. My oil pressure is fine when it starts and runs for a little while with no issue; however, when the engine gets hot (aka: after a few minutes) the oil pressure starts going down and goes into the red and my "Check Guages" light comes on when it hits the red. I replaced the oil pressure switch and it barley changed anything-it seemed to slightly, but not really. The pressure, esspecially when the engine is hot seems to be tied to the RPM of the engine. Any suggestions? It sounds like some sort of seal isn't working when the engine heats up. I'm thinking of pulling the oil pan and puting RTV black (ultra) over the entire thing to make sure that's not the issue. Let me know what you think.

 

Sounds like the bearing clearances are to big. Who rebuilt the motor? The oil pan gasket will have no effect on the oil pressure.

 

i agree. did you use a brand new pump and pickup screen? was the block hot tanked and thoroughly cleaned?