Oil Pressure Demon

[HEMIxHAMMER]

Hey Gents,
Got an oil pressure demon need some advice from the pros
2004 5.7 Hemi
81k miles
Owned the truck for 2 years
Regular oil changes I don’t drive the truck often as I drive service truck,
HERE GOES
recently my oil pressure gauge would drop and “check gauges” would come on
Shut truck down restart and gauge comes back up again for a few miles and again “Check gauges”

First step changed oil pressure switch
Same results

Put manual gauge on and start truck
Oil pressure starts at 25-30
Gradually slips down to 0 over about a minute
Turn truck off and back on same thing

So question is where to go from here, will change oil filter tomorrow and re check
But what’s next ?
Pick up screen in pan ?
Spun bearing ?
No noises or ticking

Revving engine does not make gauge move


Any help would be appreciated

 

[fastf]

If you put a manual pressure gauge I would say the pickup screen in the pan might just be blocked or you are on the verge your oil pump is about to fail.

 

[HEMIxHAMMER]

So I got it fixed, figured I’d post in case anyone else has this problem

First off - Something to think about
I HAD THE MANUAL GAUGE AND SWITCH FOR DASH HOOKED UP AT THE SAME TIME, EVEN AT 4 PSI OF OIL PRESSURE ON MANUAL GAUGE THE DASH GAUGES STILL SHOWS IS OK!!!!!

So you may have a problem and not know it, even if your oil pressure is low Since it’s a switch and
even if you have a tuner (I have Bullydog platinum) it won’t show an actual psi reading. Only way to know is with manual gauge On a 2004 5.7 other years may actually have a sender.

I put a mechanical gauge on truck
When it starts oil pressure goes up to 30psi then drops to 0 over 2 minutes

Anyways moving on
I took oil pan down to check pickup screen, all were pretty clean
If your truck is lifted (suspension) the oil pan comes right off

So only other thing left was the oil pump
And that was it, replaced it with Melling oil pump and now I have 43+- lbs at idle and up to temp

You will need to change water pump gasket, thermostat gasket, timing cover gasket, crank/timing cover seal

So hope this helps someone

 

[chrisp2493]

The oil pump was probably scored up inside. I had some engine damage and this was the internals of the pump

 

[Tyrone456]

Is all the gasket replacement necessary or it’s things you have to move so you might as well replace

 

[HEMIxHAMMER]

You WILL need oil pan gasket, timing cover gasket, water pump gasket and crankshaft/timing cover seal , all that stuff has to come off to get to the oil pump, pretty much entire front of the motor has to come off, removing the radiator and trans cooler, power steering cooler etc is By far the easiest way. Also autozone rents a tool to pull crank pulley off, I think it was $80 that you get back when you return it
The only thing I changed that was optional was the thermostat gasket, but since everything’s tore apart anyways might as well replace it, 5$ part