Engine/Transmission (1994 - 1998) Oil Pump Options

[harrisonm3]

Oil pressure is going up and down with rpm.
Appears to be getting worse.
At the low end it is still right of the left guage mark.
At the high end it is where it used to be (Right of the 40).
Gets worse as the engine gets warmer.
I can smell burning oil around the passenger side. looks to be leaking around the lift pump which was replaced a couple of years ago.
Doesn't appear to be coming from the head.
Sender is new OEM unit.
Engine oil level is appropriate and changed every 3k miles
Vacuum pump was rebuilt less than 10k miles and does not appear to leak.
Engine isn't consuming oil
No change in emissions out the tailpipe

Called around for a replacement.
Dealer wants over $400

Napa has a "high volume" unit for $67 (Must check for clearence)
-Regular unit for $30 ish

I really don't want to swap the oil pump.
My questions are: How many miles are typical for an oil pump to give up the ghost?

What pump's are recommended?

Do you think I need to pull the pump?

 

[GOlsen]

Personally, I haven't heard very many people having to replace their oil pumps, so I can't really speak as to how long they last. I've never had to replace mine, but i only have 157k.

As far as which pump to get, I would check out this one:
5. 9L 24 Valve Cummins 6B Diesel Oil Pump 4939587
It's a Cummins high volume unit. I would trust one of these more than one you could get at Napa, even though it is slightly more expensive.

 

[CharlieFoxtrot]

Put a real mechanical gauge on it first, just to be sure. Don't need to do a full install, just duct-tape the gauge to the windshield and test-drive.

 

[ata]

Like said put a real gauge on it and you will find out that the O. E. gauge is nothing more then a JOKE. On my 97 the O. E. gauge was a needle width below 40 and a needle width above 40 hot or cold. Put a real gauge on it and its 60 idle 100 plus running cold and 35 idle 65 hot running. The oil pump on the 5. 9 will normally out last the motor.

 

[hsmith]

^ What he said!!

 

[BLNRAY]

i would check the pressure regulator in the cooler,its a small piston and a spring,they somtimes stick. hardly ever hear of a pump wearing out,but it could happen.

 

[harrisonm3]

The spring was a good tenth of an inch shorter than spec. Hopefully a new one cures the issue.

 

[harrisonm3]

New spring and valve with no change.

Mechanical guage goes as low as 22. 5 at hot idle.

I think the pump is becoming increasingly insufficient.
Saw somewhere on here that spec is 10 psi or higher.

Probably going to pull the pump out and replace it.

Thought I had to drop the pan. Book says its under the timing cover. That's a relief.