Question about 1999 Chevrolet Silverado 1500

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NO HEAT 1999 GMC sierra 1500 2wd, It has heat but if I turn the fan all the way on the air is more warm than it is hot.I have changed the thermostat 2 times and checked the heater core for blockage.

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Your heating system is run by your cooling system. If your cooliant is low then you are not going to get adiquiate heat disapation to your heater core. So check the entire cooling systerm. Your water pump (low flow), hoses (leakage), you already checked the thermostat & heater core. So other than that I don't know.

Posted on Jan 15, 2009

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