long story short we changed out my buddys oil pump on his 5.3 (silverado), the outter gear inside it was cracked all the way through and both of um were grinding the housing etc. So he bought a TSP ls6 pump and just got done putting it in tonight. Changed the oil 2 times to flush any **** that was in the oil etc. Ran fine, good oil pressure but now when hes coming to a stop the oil pressure drops to 0 untill he starts moving, so its something RPM related. Only thing i can think of is the o-ring on the pick-up tube but i made sure it was not messed up and went in right. So im lost here...anything u guys can think of?

 

Bump....anyone?

 

is it a pressure problem or a gauge problem?

 

Its deff a pressure problem, we replaced the sending unit hoping it was that but no. And were getting different readings after we replaced it.

 

i was thinking that there were two diff size o rings that go on the pickup tube....one is blue and the other red i think....i know that when i replaced my oil pump it said to be sure that i had the right color o ring.....may look into that....thinking they were diff. thicknesses