Danlee126

2000 5.3L Gen III with 210K miles cam boltons. Stock oil pump
Oil pressure used to be 40psi idle 55psi cruise on highway 70psi wot for its last 100K+ life. Now it is 35psi max no matter what and gets down to 25 psi on idle.

Curious if it is the oil pump or oil sensor or motor in the oil gauge is. How to test?

Thanks

FFDP

iTrader: (2)

Pull the stock sensor and hook up a manual oil pressure gauge to that port.

If that reads what the dash reads, then you probably have a real problem like the oil pump itself or worse.

Danlee126

Thanks for the reply!
Where is it located on gen III? l'm googling at the moment.

FFDP

iTrader: (2)

Behind the intake manifold by the firewall on the drivers side.

trxmxzx

iTrader: (7)

arthursc2

iTrader: (5)

I am putting my money on the pick-up o-ring

I think Ive gone through 3 of them so far. 2 on the Tahoe (OE and then tore one doing the adjustable timing set) and on a friends Yukon we had to do an o ring. Kinda sucks to do in the truck, but with 8mm ratcheting wrench and a dremel, its possible

Toes

iTrader: (1)

RedXray

All the above...
sending an oil sample to Blackstone for analysis would detect abnormal amounts of bearing material and other metals floating around.