Freon is R12. Your 1997 Chevy uses R134 Refrigerant.
R134A
R134a
In a 1997 Ford Aerostar : Refrigerant 134a is used
R-134a
Dex cool coolant.
R-134 Refrigrant.
134a is the refrigerent used
R- 134, That's the correct freon for that car.
R134a
R-134a
R134a freon......