recently i have been wonderin if i should get a machanical oil preasure gauge the one in the dash seems to be actin funny lately on the highway it will drop when i give it some fuel and when i let off comes back up to the 40s shouldnt it be the other way around? truck is runnin great and plenty of oil in there. what you guys think

 

mine does funny crap to. when im cruising down the raod its like 35-40 ( dash gauge). then when i let off of it it goes down to like 20 and bounces around untill you take off. just to be sure you dont have a prob hook up a mechanical gauge to it and see what ya got. and replace if the sending unit is bad. imo. i know mine has good iol pressure so i dont worry. one of these days ill get er fixed. just my .02

 

yeah ill prob just hook up a gauge to be on the safe side

 

Bad sending unit.
The Cummins Motor has a large swing for "normal" pressure.
Nothing below 10psi at idle and nothing above something like 70psi for the top end LOL.
I just go through replacing my sending unit, it was saying I had 35 and Idle then would drop below zero.
New unit and she's golden.

BTI

 

nothing over 75psi? i can peg a 100psi mechanical guage

 

Me too - about 90 psi on a cold start in the winter.

I have also verified calibration of the guage and its right on the money.

 

yep same here