[Moparman1972]

I've been running my challenger about a week on the road now, and I parked it yesterday because of the oil pressure. It has a 318 with 156,000 miles on it. I never cracked the heads, just did cam and top end stuff.

Oil pressure with 10W-40 starts at 20-25 psi on startup and drops steadily to 5 as it warms. I know this is a lighter oil, and I got 20W-50 to change to, but this pressure is with correct fluid levels and STP thickener in the engine.

Increasing engine RPM over 1800 causes the oil pressure to drop to zero. Anything under that and it will creep up to 5 psi again. The car had a solid 60 psi of oil pressure before I put it on the road, running 20W-50.

Could the top end be loading with oil? Or is the oil pump totally shot?

[dave-r]

Probably worse than that. Main bearings come to mind. With that sort of pressure they are going to be gone anyway even if they were not the original cause of the problem.

[Moparman1972]

Well, that was my suspicion too, Dave, but heres how she's doing now:

Changed the oil and put in 20W-50. Oil pressure is back up to 50 psi on startup and 20-25 when warm and idling.

My theory: Clogged oil pickup tube from debris? If so, this problem will probably hit me again in a couple days. The thicker oil will probably be a bit of a band-aid if the bearings are going, too.

Dave, also, oil pressure was much better when I first started running it. It dropped steadily the past couple days. I was shutting the engine down and coasting down hills yesterday to limp it home, so I'm praying I didnt toast anything.

[dave-r]

Could have been a collapsed filter. They sometimes fall apart internally and block things up.

[Moparman1972]

Well, heres hoping it holds for the summer. If I have to pull the motor, its not going back in. I've got a 400 to pick up this weekend.