Cold air blowing and temp. gauge running hot and loosing antifreeze
Your first plan of action would be to locate the leak. This is the main source of your problems. Check under the vehicle for traces of coolant, open the hood and check the hoses, fittings, radiator, around the water pump, etc..
Ditto what Mark said! Check the heater hoses as well and not just the radiator hoses. Hopefully it's not a intake gasket, very very common on the 3.4 liter or worse a head gasket not as common.
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