Friend of mine has an 04 lb7 with close to 300k on it. The motor was replaced att about 100k due to dealer screw up. The low oil psi dinger keeps coming on. I hooked up my efi live and it showed about 7 psi at hot idle, but once I rev it up it goes right to 50 psi. I'm going to put a maual guage in it, but I can't seem to find the right fitting. It has been serviced regularly and just had a small bullydog tune in it. I don't think the pump is slipping on the shaft because the oil psi comes right up when I increase the idle speed. Any Ideas? Is it possible that the main bearings are wore out at 200k enough to cause this?
