1997 GMC Suburban Owner's Manual - Page 354

Fuel Tank Capacity (Approximate) TYPE GasolineDiesel Utility - Standard Suburban - Standard 30 Gallons ( I I3 L) Air Conditioning Refrigerants Not all air conditioning refrigerants are the same. If the air conditioning system in your vehicle needs refrigerant, be sure the proper refrigerant is used. If you're not sure, ask your GM dealer. See refrigerant charge label under the hood for charge capacity information and requirements. QUANTITY 42 Gallons (159 L) 6-72