Engine Mechanical problem
2003 Chevy Silverado V8 Two Wheel Drive Automatic 49000 miles
last month my oil pressure guage went from normal operating range (apprx 40psi) to zero. No unusual noise ever came from the engine and it continued to operate/sound/run as if nothing were wrong. I had not changed my oil in about 8000 miles. I changed the oil and filter. The oil pressure guage went back to normal. Today I started the truck and the pressure is back at zero but it sounds fine. Im perplexed. No oil pressure means noise and damage, but it seems to sound normal. Not even a tiny oil starved valve tap you might hear upon first starting the engine. What could it be. Clogged oil pump. Oil pressure sending unit. Bad gusge. Something else?