GM-GMC: .oil gauge, oil gauge, shop tomorrow

Question
I have a 95 Jimmy Gmc.  The oil gauge is low after they repaced a switch. On the reciept it stated that the psi is 6 wirh running idle at 24 is this correct.  I have to bring it to the shop tomorrow. Do you know what the correct numbers are for I quess the psi or is it psm.
Thank you so much Judy

Answer
Judy,

There are many things that affect oil pressure, which is specified in psi (pounds per square inch) in the USA.

The type of oil, the outside air temperature, and the number of miles on the engine are all factors which affect oil pressure readings.

Manufacturers give a range of acceptable pressure.  GM usually states that 37 to 60 psi is normal when driving at highway speeds.  6 psi at idle is too low unless the engine has synthetic oil in it.