Fine, fine 2.9l.......

[shorangerbird]

So, my '89 S/C with a 2.9 auto. It's not a everyday driver. It sits alot until I or my son needs to haul something. It fires off fine, smooth, no noises. just a normal 2.9.
But after it warms up and runs awhile, say 5-10 miles, once you come to a stop, it clatters like a diesel. lifters/valve train it sounds like to me. Anyway, Sometimes......when you come
to a stop and it's clattering, you can look down at the guages and the oil guage it sitting there moving back and forth with the tempo of the engine. I'm suspecting that it has a 'weak' oil
pump. Give it the gas and guage goes back to normal and steady and the clatter maybe related to it. I bought the truck used and the odometer had turned over. It "looks" like 132k, but could be
2-3332k for all I know. I've already had to rebuild the valve body in the trans as it was shifting backwards as strange as it sounds. So if it is a 'weak' pump, would you think the engine is hurt or should
I just put one in it and see what it does?

 

[RonD]

The noise is not harmful just annoying

Cause is worn cam bearings
The valve train oil is fed thru the cam bearings so as they get normal wear the oil pressure in the valve train drops

You can run a higher weight oil, 10w-40, or whats called a high mile engine oil

It helps keep oil pressure higher at idle
Colder oil is thicker so less noise, then after oil warms up more noise, going to the thicker oil(40) helps

Oil pumps were never an issue on the 2.9l, but it's possible