I have a 1999 Dodge Cummins. When I started it up today the oil pressure was reading a little over 40 and when I started driving it was on the max line for PSI, but never goes over. After the engine warms up completely the pressure will return to normal. It usually runs a little under 40 at idle and a little over 40 while I'm driving. Has anyone else had a problem like this or know what could be going wrong.

 

My pressure varies all the way from 22 psi at idle to 40ish at drive speeds to 60+ under acceleration. I don't think you have an issue.

 

I know that it is gonna fluctuate when I accelerate, but when the engine is cold the pressure reading is over 40 and when I accelerate its at the max line. As the engine warms up it returns to its normal readings of 20 psi at idle and 40 psi when I'm accelerating. It just started doing this a about a 2 weeks ago.