Oil Pressure

[Autumn]

Fully warm and at idle my oil pressure (using Mobil One 10W30) is around 40 pounds. On a long trip, it rises to around 60 pounds. Is this considered normal? Thanks for your help.

[RyanbabZ71]

sounds about right mine fluctuates from 40-60 (depending on temp, acceleration, etc.)

[mcreyaufmiller]

You should be using 5w30, that is the weight recommended by GM. If you start changing the weight, you may change things you do not want to change in the engine.

[Autumn]

Thanks very much for the replies. mcreyaufmiller, my manual specifically states that 30 weight oil is recommended. It further states if the outside temperature is not below 0 degrees F, that 10w30 is recommended. If the temp is below 0, then 5w30 is recommended. I live in South Carolina and have been using 10w30 in all my vehicles for years.....unless I make a trip north in the winter. Then, I change the oil to 5w30. I do not want to "change things that I do not want to change in the engine" so I am curious as to what I might ruin. Can you elaborate? Thanks for all of your great input.

[GM-Tech]

10w30 is fine. Your oil pressure is also fine. You need only worry if it starts dropping below 10 psi.

[gnutruk]

I calibrated my oil pressure just after the first time I changed the oil and filter.

 

After truck is up to standard operating temperature, open highway at 55 mph in 4th gear (overdrive), oil pressure is 57. Have to squint at the gauge real hard because the scale of the gauge isn't well delineated, but that's what I'm calling it.

 

Engine is Vortec 5.3, automatic tranny (Auto-Trac).

 

gnutruk

[budhayes3]

Those numbers sound the same as mine, between 40-60 (according to the factory guage), depending on conditions. If I get on it before the oil has had the chance to heat up (which I try not to do), I can see almost 80 psi. I'm curious how accurate the factory guage is...does 40=40, or 25?

 

The factory temp guage is more of an idiot light than anything...when compared to a scan tool, my temp guage was reading about 170-175 as the scan tool read 130-135. I've noticed that it seems to have about 3 or 4 increments that it moves up at a time until it levels out around the 200 mark (which is between 188* and 203* according to the scanner).