Engine/Transmission (1998.5 - 2002) No Oil Pressure!

[Ken Roberts]

3 days ago, I was driving and the oil pressure dropped to zero and the CHECK ENGINE light came :--) on as the the chime "chimed". AAAAARRRRRGGGGGG!!!! I put the trans in netural,shut off the engine and coasted to the shoulder of the road. My wife brought me a manual oil pressure gauge and I installed it in the test port on top of the OF housing. Pressure is fine. "YEAAAAAAAAAAA!" Oo. Ordered a sending unit from Geno's. Installed it today. Removed the fuel filter to give myself more room,( it needed replacing anyway). The Cummins sending unit takes a 1 1/16" socket. The OEM sending unit was 1 1/4" so I used a 32mm socket. All is well yet again!
256,000 miles later and I still think it's the greatest truck I have ever owned.
The mighty Dodge lives to drive another day!

Ken R

 

[JR]

Great to hear it was a simple fix. What kind of oil pressure are you actually putting out?

 

[Ken Roberts]

oil pressure

Great to hear it was a simple fix. What kind of oil pressure are you actually putting out?

Start up oil pressure........ The mechanical gauge on the oil filter test port shows about 40psi before the factory dash gauge even moves!
When up to operating temp, idle oil pressure is 35-40psi, at highway speeds, 70psi.
I'll double check the numbers today, but these are what I remember from yesterday.

Ken

 

[RustyJC]

Yeah, those oil pressure sending unit failures were all too common on the 2nd generation 24 valve Cummins. The "Dodge" fix turned the sending unit into nothing but a set of contacts that made the gauge a go/no go proposition where the pressure displayed had nothing to do with actual engine oil pressure.

Rusty

 

[azpete]

It's so funny, mine has been unplugged for years and the gauge always shows 40PSI.

 

[drag racer]

Yeah, those oil pressure sending unit failures were all too common on the 2nd generation 24 valve Cummins. The "Dodge" fix turned the sending unit into nothing but a set of contacts that made the gauge a go/no go proposition where the pressure displayed had nothing to do with actual engine oil pressure.

Rusty

Very interesting! I still have the OEM sensor, so my gauge reading does vary, but for a time I had a remote oil filter setup on with an analog gauge, and I was surprised to see that the actual pressure was a lot higher than what the dash gauge says - by like 20 psig or so.

 

[Road Dog]

The story goes that the oil pressure varies a lot with engine rpm which led to a lot of warranty service claims which led Chrysler to disabling the analogue gauge in software.