No Oil Pressure 2009 Chev Silverado
My Chev is a 5.3 & has approx 420,000 km on it. New transmission about 3000 km ago. My engine light went on about 130 km ago when I was in middle of nowhere. I checked oil, it was ok. I continued to drive and gauge dropped from 12 o'clock position (where it normally sits) to 9 o'clock position, waveered between 8 & 9 the rest of the way home. Got to town, and gauge rose a bit. When I shut off motor it was back at 9 o'clock. Sat for 3 days. Started today, warning lights came on saying basically to shut off motor, which I did, so couldn't use scanner. I class it as inoperable right now. Temperature outside has dropped from Around -10 to -29 C in those 3 days it sat. Can't call shop cuz it's Sunday, but would like some kind of idea before I call. Expensive fix or not??? Thx. . .