Hey everybody! I have a 2000 Silverado 1500 with 216k miles on it. When I was driving from Columbus, OH home yesterday (2 hour drive that took me 3.5 hours), my engine temp gauge hit red after a short time (half hour) of driving. When I turned my heat on full blast, the temp went down, but not very much. My friend and I both think its the thermostat, but what do you think? When I drove it today (7 miles down the road), it was almost to red after the short distance. The coolant is at the right level, and I dont see any leaks anywhere. If I need to replace it, do I need to drain it completely or just enough so its out of the thermostat housing? Thanks so much for your help!