Question about 2000 GMC New Sierra 1500

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2000 GMC Sierra 4.8L V-6 - AC blows warm air

I have had this truck for almost a year. Bought it with 125k miles. It now has approx 148k on it. Last summer in 100 degree plus heat and running AC the thermostat shoots way up when on the freeway beginning to pull a grade. Turning the heat to maximum temp and running fan on high gets the temperature gauge back down in about 3-5 minutes...A couple of months ago the AC stopped blowing cool air...2 weeks ago the Lube place flushed out my cooling system and replaced the Dexcool product (the Tech said there was regular coolant in it - Bad!). 2 days ago when driving home from work, the low coolant light came on (first time since I have had the truck). the next day I took it to the place that flushed my cooling system and they noticed that the rear crank pulley belt was broken (no overheating). Is that belt related to no cool air blowing in my AC?

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Yes, Depending on where that belt runs in your setup.If it runs to your a/c compressor, it has to pull the compressor pulley to circulate the freon through your a/c system.If your a/c compressor is not pulling,you will get nothing but hot air.The a/c compressor is the heart of your a/c system.From the sound of it,replace that belt and it should be fine.Hope this helps.Have a good day.(p.s. you always want to keep dex-cool in your vehicle being that it is a GM vehicle after 2000)

Posted on Jan 18, 2009

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Never seen a truck like this ,iam in spain but from the sound of it one belt drives a/c and another the power steering and altenator ,pos water pump as well but this could be driven by the timing belt .As i said i have never seen one of these trucks .If i had it in front of me i could soon tell you .

Posted on Jan 18, 2009


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