Oil Pressure Fluctuation

[aragu36]

My ISB oil seems to go from middle at start to about 25- 40 % of gauge
on highway and 10-15 at idle
all within normal but just curious
I just changed oil 15-40
Is this normal higher pressure is better im sure
can I change to a different grade oil?

[AFChap]

Not sure what your question is ...sounds like normal variable gauge readings to me.

[GaryKD]

Hi aragu36,
My ISC does the same as your engine. Drop this from your list of things to worry about.

[spike45]

ISB, ISC, ISL engines have oil pressure in the range of 45 PSI at engine rated load speed. It is not unusual to see the pressure drop to the 10 -15 PSI range at hot low idle speed. Increasing oil viscosity to get higher oil pressure is self defeating. Increasing the viscosity (internal friction of the fluid) will result in higher pressure but less flow to the bearings. Don't go there!

[Mr_D]

Agree with the above.

Except today I started our ISC, it was in the upper 40's and I didn't run the heater. The oil pressure was above 100 psi on high idle (1000 rpm) but I know that it drops as the engine warms up. I'm using a 9009 filter.