When driving at ~70 mph, the oil pressure drops the pressure at idle and then builds back to normal. This happens at irregular intervals. Engine revs are constant when this happens. I also have a problem with cold engine rapping when the temperature drops below 20 F. I switched from 5W-30 oil to 10W-40 oil. This has not stopped the rapping, but lessened the oil pressure problem.
When driving at ~70 mph, the oil pressure drops the pressure at idle and then builds back to normal. This happens at irregular intervals. Engine revs are constant when this happens. I also have a problem with cold engine rapping when the temperature drops below 20 F. I switched from 5W-30 oil to 10W-40 oil. This has not stopped the rapping, but lessened the oil pressure problem.
- nhchemist, Kensington, NH, US