Brian W Burdick
06-09-2006, 02:17 PM
2003 GMC 2500 HD Duramax/Allison 144,000 mi
Oil pressure gauge sometimes shows low oil pressure and low oil pressure alarm sounds. Teed into oil pressure sending unit location with mechanical pressure gauge. Shows less than 8 psi (55kPa) at idle when low pressure is seen on truck gauge. Shut off truck for 10-15 min., restart, oil pressure normal(mechanical gauge still hooked up)25 psi (172 kPa)at idle,60 psi(415 kPa) at 1500-2000 rpm. This low pressure condition sometimes repeats itself within a short time (minutes or a few hours) or maybe not for a day or two. This always happens when engine is at normal operating temp. New sender installed when first at repair shop (not GM dealer).Repair shop says wrong oil(Mobil Devlac)and filter(Fram PH 9100) so insisted on changing to GM filter and oil. Still has same problem. Could this be oil pressure relief valve sticking? If so, what is the cure? What else?
Oil pressure gauge sometimes shows low oil pressure and low oil pressure alarm sounds. Teed into oil pressure sending unit location with mechanical pressure gauge. Shows less than 8 psi (55kPa) at idle when low pressure is seen on truck gauge. Shut off truck for 10-15 min., restart, oil pressure normal(mechanical gauge still hooked up)25 psi (172 kPa)at idle,60 psi(415 kPa) at 1500-2000 rpm. This low pressure condition sometimes repeats itself within a short time (minutes or a few hours) or maybe not for a day or two. This always happens when engine is at normal operating temp. New sender installed when first at repair shop (not GM dealer).Repair shop says wrong oil(Mobil Devlac)and filter(Fram PH 9100) so insisted on changing to GM filter and oil. Still has same problem. Could this be oil pressure relief valve sticking? If so, what is the cure? What else?