Question about 1999 GMC Yukon

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I have a 99 Yukon. When I bought it, the AC did not work. Turns out there are two AC systems. One operates the system that cools the front of the passenger compartment, the other cools the rear. It would have cost an additional $1000 to fix the rear system, so I didn't have it repaired. Now it is closing in on winter, and I noticed that the rear vents only blow cold air when the heat is turned on (with the re-circulation on or off). Are there two heater cores too? If not, is there a way to direct some of the hot air in the front to the rear of the passenger compartment? It is a 99, so I don't mind a duct tape Mcgyver solution.

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There are two heater cores. autozone.com has a great turorial on how to replace. You could try to blow low pressure air through the heater core to clear out any gunk.

Posted on Nov 11, 2010

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1 Answer

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1 Answer

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