Do you have to drain the freon change heater core on a2001 dodge ram pickup?

No, you do not have to drain the refrigerant (Freon) to change the heater core in a 2001 Dodge Ram pickup. The heater core is part of the vehicle's cooling system, not the air conditioning system. While both systems use a type of coolant, they are separate and distinct. You will need to drain the coolant from the engine's cooling system to replace the heater core, but not the A/C refrigerant.