Q: Engine overheats, heater blows out cold air, coolant boils in radiator

asked by on October 17, 2016

My engine overheats and the coolant boils and the heater in my truck blows straight cold air. I at one point drained my coolant completely with the plug on the bottom of the radiator and seen that it was dirty. I'm wondering what it could be? Do a thermostat replacement? Do a radiator complete flush? Or do both thermostat replacement and complete radiator flush?

My car has 177438 miles.
My car has an automatic transmission.

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