How many pounds of freon presure in the ac system for a 2009 avalanche?

The pressure on the low side should be between 35 to 45 psi and the high side should be between 200 to 250 psi depending on the outside temperature...............

The amount of freon (R134a) for a completely emptied system will be 3.0 pounds for a dual system and 2.0 pounds for a single system............