I purchased the truck new and it has always run at 210 degrees. They are saying that it is ok to run at 220-225 degrees. is this a true statement or should I be seeking a new mechanic.
My car has 38000 miles.
My car has an automatic transmission.
The engine will run hotter with the A/C running and the heat from the condenser through the radiator. You may want to make sure the cooling system is serviced with fresh coolant and the engine fan clutch is locking up all the way. The temperature of 220 to 225 is okay but a little high for the engine on your GMC Sierra 1500. If you’d like a fresh pair of eyes on this issue, consider YourMechanic, as a certified technician can come to your home to diagnose your temperature concern.