Oil Pressure At Idle 5.3l

[zgranj]

Hi, I have a 08 GMC 1/2 ton with a 5.3L and I noticed the oil pressure reads at 20 when idling at around 500 rpm's. Is that normal? When I'm driving at highway speeds it hovers at around 40.

 

Thoughts?

[georgecdisc]

Hi, I have a 08 GMC 1/2 ton with a 5.3L and I noticed the oil pressure reads at 20 when idling at around 500 rpm's. Is that normal? When I'm driving at highway speeds it hovers at around 40.

 

Thoughts?

Cold Idle: Just under 60 (800-1000 rpm)

Warm Idle: Just under 40 (~500 rpm)

Driving: Little over 40

[cerbomark]

i m sure it s ok. Differences in temps. and oil weights will make that vary also. Mine is Cold, Idle (63 air temp) , over 40.

Your presure should jump up once the RPMs go up.

[Zembonez]

Keep in mind that the gage on the dash is only an indicator. Pay little attention to the actual numbers on it. Hot engines often show 20 - 25 psi on the scale at idle and about double that it highway speed... The pump is mechanical and dumb. It just pumps more volume the faster it turns. There is a bypass valve that limits the amount of pressure it can build at high rpm.

 

Yours is just fine.