The sending unit on this engine should have been moved to a remote hose. There should be a ground wire from the metal part of the sender to a ground on the block. Often this ground wire is missing.
The sender unit is on a remote hose attached with cable tie to filler neck, but there is no ground wire to anything will look at it tommorow or Monday bought a guage that reads in psi so will put it into oil galery where idiot light sender is to compare psi in reference to cab guage thanks.
All I can find is not less than 10PSI at idle and not less than 25PSI at 1300RPM and or MAX torque. It is likely crank dipping and beating on the oil when turning and side hill. This will put air into oil and lower the pressure. We found oil level to high on the first M11s so this was common. Cummins was to install new dipstick to get max oil level down. Crankcase capacity is 32 quarts and 35 counting filter. I would drop your level to add mark or drain and refill to check if dipstick is right. Dustyr72 may still have dipstick that has full mark to high on dipstick. Supposedly the add mark stays the same as before. Good luck
NDDan,just traded the R60 for another R72(97 model). this one has a dipstick that just pushes straight in. on the 96 it has the kind that you twist the knob on top.
This full mark on dipstick was changed sometime in '97. Evidentally later than your '97. You best carefully monitor oil put in at next change. Maybe swap the dipstick and holder from '96 to do a little comparing. I'm sure you can still get newer twist lock diipstick that should be right. Good luck