2005 GMC C2500 Low oil pressure on cluster display

2005 GMC C2500
60,000 MILES • V8 • 4WD • AUTOMATIC
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COLMHUR
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I'm working on a 2005 GMC 2500HD with a 6 liter v8. I'm getting a Low oil pressure warning on the I/C display. I have checked the oil pressure with a manual gauge, and I'm getting 5 psi at idle. I have replace the oil pump, o-ring seal on pick up tube. I'm still getting the low oil pressure. I tried a new O/P sending unit, no change. Any ideas??
May 7, 2009 at 9:28 PM
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BRIAN 1
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check these things,If the engine oil pressure is below specifications, inspect the engine for 1 or more of the following conditions:
• Oil pump worn or dirty

• Refer to Oil Pump Cleaning and Inspection .

• Oil pump-to-engine block bolts loose

• Refer to Oil Pump, Screen and Crankshaft Oil Deflector Installation .

• Oil pump screen loose, plugged, or damaged

• Oil pump screen O-ring seal missing or damaged

• Malfunctioning oil pump pressure relief valve

• Excessive bearing clearance

• Cracked, porous, or restricted oil galleries

• Oil gallery plugs missing or incorrectly installed

• Refer to Engine Block Plug Installation .

• Broken valve lifters

• Repair as necessary.

If the oil pressure reading on the J 21867 , or equivalent, is within specifications, inspect for the following conditions:
• Plugged or incorrect oil filter and/or malfunctioning oil bypass valve

• Malfunctioning oil pressure gage or sensor

here is the oil pressure spec,Oil Pressure - Minimum - Hot 6 psig at 1,000 engine RPM

18 psig at 2,000 engine RPM

24 psig at 4,000 engine RPM
if all this checks good you might have a problem in the guage itself in the IPC.post back with any other questions.
May 8, 2009 at 12:49 PM