I have low oil pressure -20 on my 01 2500hd 8.1. I changed oil pressure sensor and oil pump still same what else can it be

[Sgutierrez]

[Jsdirt]

Could be time for a new engine. How are the big-end bearing clearances, for starters?

[Duelin]

I would start by installing a mechanical oil pressure gauge. That eliminate a lot of questions. Like is the new sending unit working correctly "all the parts you buy today is risky", is the wiring ok, is the gauge reading right? If it still reads the same then I would try a heavier grade oil. If the pressure comes up with the heavier grade of oil then its like Mr. Dirt said, time to look at the bearings and check the wear on the crank.    May the luck of the Irish be with you .     Good Luck

[Jsdirt]

Yep, easy stuff first! I've been out of auto repair for a year, and I'm already forgetting!