I am posting this to help others, so they can compare their gauges to know what pressures they may have. I will post this in the FAQ.

Just like many others my engine oil pressure switch/sending unit failed. I was getting extremely low engine oil pressure and sometimes at idle it would drop all the way down and the light would come on.

So I got a mechanical gauge to test where my oil pressure is just in case.
See below what the oil pressure were at various times. 5.9 Magnum 180 Deg thermostat, 40,000 Miles since rebuild, but don't think the oil pump was replaced.

Cold start 80 Deg outside temp.
Idle 55 Psi 3,000Rpms 65 Psi

Normal engine temp. 180 Deg thermostat.
Idle 15 Psi 3,000Rpms 55 Psi

Warm start after 30 min cool down.
Idle 25 Psi 3,000Rpms 55 Psi

2 hour of hot heat high loads 180 deg engine temp.
Idle 13 Psi 3,000Rpms 50 Psi

Here are pics of where the gauge is at the above pressures with a new Pressure sending unit.

This is Cold start up at 55PSI


This is Normal engine temp with 180 Deg thermostat. 15 Psi.

 

mine droped to zip again so it needs a new engine now not just a rebuild like before




by the way i just grrad fom air force basic today

 

Mine will go higher than that on a cold start up and when im driving down the road.. When it is warmed up and idling it will be like yours. Sometimes it will drop to the 15psi while driving down the road and them it will go back up.

 

Congrats young man!