Oil Pressure - What is Normal ?

[1999BlueTahoe]

So I’m looking at possibly purchasing this ‘01 Tahoe with the 5.3 and it’s oil pressure readings made me pretty nervous. Cold start pressure was around 60psi+ and would read right below 80psi at interstate speeds and low throttle. To me, either the gauge is not reading properly or there’s something wrong with the oil system. Would love some input. Thanks.

 

[wsteele]

Sounds like maybe a defective sending unit. Kind of fussy work changing it. Before I bought it, I would put an analog gauge on it and verify the pressure was fine and the sender/gauge was off. There are tons of YouTube videos on how the change the sender. If you end up buying it, I will fine my favorite one and post it.

 

[Geotrash]

It's also possible that there has been some engine work on this Tahoe that included replacing the oil pump with a higher volume/pressure unit. If so, that can have some complications as well. It would be interesting to know the service history of this truck if any of it is available. Or perhaps the seller may know if that kind of maintenance has been done.

As Bill says though, you really need to get a gauge on it to know for sure. If that pressure is indeed accurate, it's high. Normal for these engines is 60 on the high end (cold oil, cold engine, higher RPMs) and 20 on the low end (hot oil, hot engine, at idle).

Another idea is that it could simply be an indication problem. One way to check that is to get a Tech2 or equivalent that can read the actual oil pressure values being provided to the computer by the sender, and compare that with the gauge reading on the dash.

 

[Efingee]

Honestly, I think 7 or 8 psi is around where it will trigger the cel and warning for oil pressure problems. If you see that then check the oil level and change the sensor and screen first. I would be satisfied with 20 psi at warm idle with an increase upon acceleration. 60psi is about where they should max out. Definitely wouldn’t be worried about 20psi at warm idle.