why do i have such poor heat in my 1981 gmc 1500
i have replaced the thermosat many times over the years, yet the heater still does't put out. replaced heater core 3 yrs ago, and has a new radiator. help it's winter and need heat. please note; 1981 not 1988.
did you try replacing your hoses it could also be you heater switch in you truck too mine was a simple vacum leak
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