Check the thermostat or the radiator. The thermostat could be sticking or the radiator could be plugged.
you may have a bad thermostat,replace and see.
The rear window defrost/defog heater grid.
You most likely have a leaking heater core inside the truck.......
Try flushing heater core Try flushing heater core
not getting heat into cab not even enought to defrost windows i have changed the heater core an thermostat an back washed the core and still nothing
The doors are electric. You most likely have a broken door inside the heater box under the dash.
i just replaced the thermostat in 2004 Chevy truck heater works fine now
It will overheat at idle.It will overheat at idle.
First you need to make sure the truck is cool,so you do not get burned. Release any pressure in the system by removing the radiator cap, being careful not to burn yourself. Remove the two heater hoses at the firewall. Cap the two tubes on the heater,so you do not spill antifreeze in your truck. Remove the heater core access cover from under the passenger side dash(five screws hold it in place). This is done from inside the truck. Then pull the heater core rearward and down to remove it, carefully. Put the new one in the same way you took that one out. Fill your radiator with a 50/50 mix of antifreeze. Run the truck with heater and recheck your radiator fluid after it cools. Be sure to check for leaks.
replace heater core in a 1991 Chevy work truck 1500
The heater will stop getting hot when you're low on coolant. If the coolant is low enough the engine will overheat and it will be severely damaged.
need diagram for heater core for a 1994 Chevy truck.