I have a 1999 Ford Ranger (two-wheel drive, 138,000 miles). Twice in the past year I have had this happen: I notice truck is running very loudly/rough, and notice the oil pressure gauge shows no pressure. The first time, I pulled over, had it towed. At the service station they started it up, gauge was normal. I took it to the dealership, they replaced the sending unit, could not explain why it might be running rough. Today: same thing: gauges normal when I left home, and hour later I notice it running rough, gauge says no pressure. Pull over, turn it off, restart: still no pressure. Turn it off and let it sit 15 - 20 minutes, start it up: gauge is normal, runs smoothly.

What do I have them check next?

 

You might have sludge or something in the pan getting picked up by the pick up screen blocking it killing oil pressure. You shut it down it falls off you have oil pressure again. Happens to 4.0 sohc with all the plastics from broken cam tentioners in the pan.

 

"You might have sludge or something in the pan getting picked up by the pick up screen blocking it killing oil pressure. You shut it down it falls off you have oil pressure again. Happens to 4.0 sohc with all the plastics from broken cam tentioners in the pan. "

Is this something an oil-change would fix?

 

Mine did that when I had the PVC tube bent and there was a kink in it.