I plan on changing the oil after ~1000 miles, less if it gets really dark. Also had an engine flush done which seems to have helped.

Fingers still crossed. Engine seems to be running fine. It's not making blue smoke, truck creeps fine, and it accelerates fine.

May have another flush done just to be sure. There was a lot of crap in the oil pan.

sounds like you found the issue. with that much sludge (and obvious neglect) you had no choice but to declare war....

JP

2002 dakota 4.7 same issue I was hoping someone ekes had the same problem I thought it might be sluge on strainer or bad pump but when pressure came back after turning it off a n d on couple times then dropping to 0 after a few seconds like something was clogging strainer i thought it strange to be up and down.like that most of the time if pump is bad it just stops all.together. oil pumps dont usually come and go like that with out making a noise.first indicating a stripped gear etc. Or at least thats been my experience but u never knoe so the other post about sludge has me hopeful.that that's my problem as well but I've chs n get the oil a few times I just bought it as well few mths ago been a damn good truck. I put new injectors and coils in it couple mths ago truck.was not well mech maintained. And i replace the rocker arms as well.it was not too dirty when I was in there though.but it might be in the oil pan. I hope its sludge in the.pan ill find out tomorrow wl tell me .I'll flush and drain and fill.and start fingers crossed

Deleted my response cause I obviously had not read thru OP's post properly. Was at work and not paying full attention. My bad.

My 2000 Dodge Dakota is doing the same thing. (Check gauges light comes on and oil drops to 0. I’ll get the pan, oil and filter cleaned. I’ll be back to see if that was the culprit.

One time recently, my 2000 4.7L oil pressure gauge randomly went to zero. The "check gauges" idiot light came on. I was driving down the road when this happened. No sounds, no noises, running fine. I pulled over and shut off the engine. After about 10 sec., I restarted the engine. Oil pressure was back to normal. This happed once, and then nothing since. Don't know? The engine has had some sludge from past neglect. Could have been a piece of junk in the pick-up? Or maybe the 26 year-old oil pressure sensor is on it's way out? Don't know?

Most likely the sensor. I've replaced mine a few times now. They start leaking too. Always used Mopar. The last one failed really quickly and the dealership I purchased from sent me a new one.