05 having oil pressure problem. Usually runs around 50Lbs cold 15 warmed up. After the engine warms up, and I come to a stop-First the check guage's warning light/bell go's off, then approx. 2 seconds later the oil pressure guage plummets from 15Lbs to zero. A very slight increase in RPM from idle bring's the guage rapidly back to 15Lbs. I have checked oil level repeatedly, and changed filter(after recent oil/filter change). I don't want to replace the oil pressure sender without more input. Thank you for any help you can give.

 

Remove the oil sending unit and install a test guage.
That will atleast tell you if it's a mechanical problem.
Get this checked out fast!
Got any warranty left?

There is also a TSB that applies for your condition
Models: 2007 (D1/DH/DR) Ram Truck

Overview:
This bulletin involves selectively erasing and reprogramming the Engine Control Module (ECM) with new software.

Symptom/Condition:
The following enhancements are included with this software:

Improved engine cooling (radiator fan activation) and prevention of possible engine
overheat. When coolant temperature faults are present the radiator fan is enabled
(turned on) during vehicle operation.
Correction to oil pressure reading when engine is operating at higher engine
temperatures above 91°C (195°F).
Improvement to the Temperature Sensor Rationality Test to prevent possible false
test failures and their following related Diagnostic Trouble Codes (DTC's):
a. DTC P0071 - Inlet Air Temperature Sensor Rationality.
b. DTC P0111 - Intake Air Temperature (IAT) Sensor Rationality.
c. DTC P0514 - Battery Temperature Sensor Rationality.
Additional Water-in-Fuel (WIF) warning added to indicate that the operator has had a
WIF DTC P2269 and has continued to operate (drive) the vehicle in excess of 500
miles without draining the water from the fuel filter. The following is the new WIF DTC
that has been added:
a. DTC P0169 - WIF Too Long Error
**Improvement to the Fuel Pressure Rationality Test to prevent possible false test failures and the following related Diagnostic Trouble Code:
a. DTC P0191 - Fuel Rail Pressure Sensor Circuit Performance (2004.5 to 2005 M.Y. vehicles).**

 

The update on the oil pressure problem is... A local mechanic has ran the truck with a mechanical oil pressure guage. It appears that the oil pressure problem is atleast partially mechanical in nature.Oil pressure dropped as low as 6lb on mecanical guage. I have worked in automotive machine shop's in the past and am fully aware that bearing clearances are a common cause of low oil pressure. It is my hope that possibly replacing the oil pump might fix my problem. It was also mentioned that some type of oil pressure relief valve might be the problem. If anyone is wondering if I am trying to avoid the dealer the answer is yes!. Is there a good book that is dedicated to the cummins ISB diesel?. Thanks again for any helpful input.