2003 GMC Yukon no oil pressure suddenly, no noises

2003 GMC YUKON
133,000 MILES • V8 • 2WD • AUTOMATIC
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SPENTONBARGAINS
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We crossed the Kansas border on our way back to Ft. Worth, Texas....car running fine....no noises...
we stopped for gas....when we started up again...no oil pressure!...we drove a block...didn't help...the guage, beeper and message on the screen all said no oil pressure.....After towing 450 miles..... the mechanic said, "not worth trying to fix the oil pump, we checked the inflow tube from the pan to the pump (external to the oil pan)..."Needs a new engine...$4700...!!....Now I had put on an AMSOIL
Bypass onto the cross member of the car, at 2,000 miles when I bought it new (so that I could get 400K+ out of the engine)...could it be the problem...so disappointed..
Mar 22, 2009 at 10:01 PM
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JAMES W.
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Does the engine "rattle" when you start it up? What did your mechanic say is supposed to have happened that you lost oil pressure? Please advise.
Mar 23, 2009 at 12:37 AM
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SPENTONBARGAINS
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no noises, just running fine...mechanic says he
thinks it turned a cam bearing....that the oil pump replacement would be too costly....and it might then not solve the problem, and we would have to replace the engine anyway... but there have been no noises.
Mar 24, 2009 at 11:13 PM
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JAMES W.
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I'm having a little trouble with the cam bearing theory. Even if you spun a cam bearing, you'd still have oil pressure.
Did your mechanic screw in an actual oil pressure gauge in place of the OP sending unit to check pressure?
Keep me posted. This one is going to be interesting.
Mar 27, 2009 at 12:41 AM