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Anonymous Posted on Jul 07, 2010
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I have a 1998 gmc sierra and mt oil pressure gets low after engine warms up ive been told its my rod and main bearing but i think it could be the oil pump but im not for sure please help

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Duane Wong

Duane Wong

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  • Chevrolet Master 6,826 Answers
  • Posted on Jul 16, 2010
Duane Wong
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Well, they may be right in saying that normal engine wear is causing this problem as the distance between the bearings and the oil passages gets bigger, the oil pressure drops.

If you want to spend the money on a new oil pump, you can, but there is no guarantee that will solve the problem.

You're right, the oil pump's passages might be wearing along with the rest of the engine causing this gradual low oil pressur problem.

Have you had the oil changed along with the filter to see if maybe there's a circulation problem in the engine?

I had low oil pressure on my 1997 Cadillac Deville Limousine, that was intermittently flashing the low oil pressure light.

I read that it's recommended to change the oil to the proper viscosity and that seemed to clear up my problem on my GM Northstar engine.

It's worth a try.

Good luck on this repair.

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I have a 1991 gmc sierra and my oil pressure is dropping down to zero and it has began to knock it was not knocking or anything until i noticed my brake light was flashing now i reset the computer but
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Thank you for using fixya and sorry for the bad news.
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