My wife has a 2002 Durango. I was driving it yesterday and noticed the oil pressure gauge was at 1/4. I thought I better check the oil ( you never can tell) before I could stop ,the pressure dropped and bottomed out. I shut off the engine and stopped the car. I checked the oil, it was fine. I started the car and it took about 30 seconds for the pressure to come back up, it pegged at 1/4.
I ruled out the sender and concluded it was indeed losing pressure. I drained a qt of oil and put in a qt of lucas oil additive, changed the oil filter to see if that would help.
Pressure was way over 1/2, the engine was humming and not noisey like before. This morning I started the car, it took a little bit before the pressure came back up. It was well over 1/2 again.
My son a parts guy, thinks that the check valve on the oil pump is getting stuck.
Anyone have any ideas

SURE SOUNDS like a sending unit to me.

Try putting a mechanical gauge on it to check this condition.

We ruled the sending unit out. Can't mistake the sound of an engine with no oil .....

Sounds like a sludged up motor on its way out.

I googled the problem and found quite a bit of sludged engine problems but the symptoms don't fit. You think a motor flush should be my first step?

Haven't checked it. The car doesn't burn any oil and it has only 60+ miles on it Do you think I should drop the pan?

I bet it was your filter. Same thing happened to me with a fram filter. Have you seen how they are constructed? I won't buy another one. Napa/WIX only for me or some higher quality filter.

It's a bit involved to drop the pan, but that's what you'll probably be doing, and hopefully find a plugged screen and no crank damage yet. If you have the 5.9, you will not be the first to have the pickup plugged, and I suppose the 4.7's could do it too.

Could be the by-pass in the oil pump is stuck, which
means pulling the pan. Change the oil filter first
and if the same problem is there pull the pan

Suggestion Change oil change to another brand of oil filter I had a sludged 360 that had a 1 inch of carbon built up under the intake. I started changing oil every 500-800 miles
I used Marvel Mystery oil or a qt of atf built up from 20-25psi at speed to near 55psi. Got rid of noise and solved the problem. Another 318 I had bought had zero due to plugged pickup. I had to clean out twice but got pressure back to normal with the purchase of new gasket set. Depends on the chance your willing to take, which to do as all that detergent can lead to plugged pickup tube/ If valve seal particles forget it You pull the pan

That's what I've been reading, clogged pickup. It seems that my Dodge Durango along with a few other models are prone to clogging the lubrication system, even with regular oil changes.
I think I'm going to try to flush the engine with seafoam or somthing like that a couple of times, keep a sharp eye on the oil pressure and use a synthetic ...... It definitly got better with the new oil filter. I sure don't want to drop that pan ...... unless I have to .... it's a 4 wheel drive...

IF it is sludged up ... that sea-foam will just LOOSEN more of the garbage up and plug-the-pickup worse.

GET a read with a REAL gauge and be prepared to pull-the-pan.

You didn't say what engine, I'm going to assume you have the 4.7, I have done a few of those for the pickup clogging. You did the right thing in shutting it off right away. You wouldn't believe how many people come in and say "the oil light has been on for a week". They are the ones that usually need an engine. You might be ok, but I'd pull the pan before you start it again. If there's gritty sand like stuff in the pan,clean it out and replace the pickup tube.If there isn't you have other problems. The 4.7 is fairly easy to get the pan off.

Does anyone know the procedure for pulling the pan? It's a 4.7 4 wheel drive ..... Thanks for all the info everyone .....

i dont know the complete procedure,but the first thing is to remove the front diff,driveshaft,6 bolts at eah half shaft/axle some bolts on eah side by the engine mounts and its out,that leaves the pan in the open
butch

4.7L oil pump is not in the pan. Its behind the timing gear, pan still has to come off for oil pick-up. Big job,if engine is sludged up a reman unit may be your next move. Oil changes every 3K are required.