sledsel

My 99 with 100,000 mi on the 5.4 recently started the common oil pressure problem when the engine was cold. This problem started after a recent oil change. 10-20 seconds after startup the pressure would come up to normal. thought maybe the sending unit was to blame. Yesterday on the freeway, oil pressure dropped to 0. Pulled over, checked oil, it was full. I restarted the truck pressure came back to normal. I drove the truck home and a block from my house, the pressure dropped again and motor started ticking. No oil pressure now. Thought maybe a blockage in the new oil filter so I changed it again. No pressure and louder tick this time. Out of ideas...

GMan

Blockage in the pump?

f1fiddys

I had this happen to me,The pressure relief valve in the oil pump picked up some type of dirt in the engine and stuck it self in the pressure relief valve not letting the oil pump build proper pressure,my engine was a different modle than yours but i think they all operate basically the same,It may be something to check if all else fails,Best of Luck.

sledsel

Thanks for the replies. Truck is in the shop now for new oil pump. Hope there was no engine damage...