My Dakota has SUDDENLY developed this action. It also will give a momentary lifter noise when started hot. None of the actions have occured before. 76,000 miles 5.2 engine with darn nice maintenance.

Engine runs fine without any hesitation/noise or power problems.

I can recover pressure by increasing rev to 1200+

I unscrewed the sending unit and put on a mechanical and YES there is no pressure at idle when hot. Strange how it happens when stopping.

As a by the by thought.. I had to replace most of my cooling system radiators and exchanger in the dash due to casting crud residue plugging the fins.

Since I believe in my heart that I suffer from low oil volume and since it was a sudden onset, I think its on the pickup site manifested as sludge/casting crud combo plugging my pickup screen.
Could be a small airleak in the pickup tube also. We have had some horrendous potholes so I'll check the pan for dents and damage..

I plan on doing a compression test first the pulling the pan for exam. Once the pan is down for inspection I'll put in a high volume pump(only15.00 more than a standard) and a new pickup ..

Any other folks had and cured this problem???

 

Does anything happen when the oil drops? Mine did this for a bit than it just went away. Maybe try changing your oil and filter. Filter could have sucked something up./

 

ever drop the pan, see what ya got in there, bad pump/ screen, what kinda psi you get say at 3500 rpm?

 

What is your oil pressure at 2000 RPM? And then what happens as you watch the gauge and slowly let the engine down? Does it fall gradually down to 0, or is there at a point in the RPM range where once the engine slows down enough, the oil pressure immediately falls to 0? And at what coolant temperature does this start? You said only when hot...when cold, I assume you have proper oil pressure?

 

I have normal pressures.. say 55 psi cold and 40psi running..
I have changed oil and filter w/o change( But, I do feel better now I checked the oil levels which were normal.)

Compression check will come before dropping the pan..

FYI it was so sudden I thought I popped a lifter.. but in that case it would never recover.

still stymied.

 

pressure drops to ZERO for a few seconds and then I rev to 1500 and it comes back Engine temps are normal

 

I've heard of people changing oils, filters. Sometimes it's for whatever the reason a bad filter.



IMO I believe there's something going on with the pick-up.

 

I have a 98 ram van 3500 RV. at around 40,000 mi, I changed oil brands because my old favorite, kendall 10w/40, stopped making straight dino oil. The oil pressure dropped at any relatively low rpm. As soon as possible, I changed to Castrol 10w/40 dino. The oil pressure went back to normal. I took the case of whatever back and got my money back. I'll try to remember what the bad brand was and get back.
Art

 

Well I went to my fav mechanic and stayed till we dropped the pan

..Went out and got a Mellen HV pump..Dropped the pan and found.....WORN OUT ROD BEARINGS at 60,000 miles allowing excess oil to drain away at idle.. caught it just in time.. the fix ( Rod and main bearings and HV pump ) cost me $575.00 (mechanic installed labor included)today and I was happy as all getout that I didn't wait and spin one of those bearings or worse yet- sieze the engine in the middle of nowhere.

The mechanic picked up on my statement that I thought I heard lifter noise when shifting from 1st to 2nd also....a classic rod bearing symptom and I missed it completely..My Bad.

The HV pump is a must if you drop the pan for ANY reason.. Magnum engines are starving for oil by design with even low miles. Your clue is Mellen makes the HV(25% more flow) as a STANDARD replacement pump. Its worth the $15.00 upcharge for sure.

Suggestion.. oil pressure probs- check actual pressure with meter- if ok DROP PAN and look.

 

So how many miles does your engine have? In the first post, you said 76,000, and in the last post, you said 60,000. Either, though, is awfully soon forcrankshaft bearings to be worn. What is the service history on this engine? Type of oil/filter? Change interval? My 5.2L is at almost 170,000 now, with good oil pressure, at least according to the factory dummy gauge.