As this was the year of the switch, it can have either. There should be a sticker somewhere on the unit listing what it has. Any A/C professional can tell you.
This is the transition year. It can be R12 or R134. It is listed on the unit. The fact that R12 is no longer being produced makes it extremely expensive. Convert it to R134.
They should never be mixed.
1993-95 for most.
Uses no Freon which is R12. Uses R134 refrigerant.
Freon is R12. Your 1997 Chevy uses R134 Refrigerant.
R12 Unless it was converted over to R134. There should be a decal if they did the conversion.
Unless It Has Been Refitted For R134 It Will Use R12. Best Way To Work This: Have A Good A/C Tech Update To R134 And Test Your System. You Will No Longer Be Able To Get R12 Well Some People Have Some Stashed About ( Cost Is High ) There Is Supposed To Be A Freon That Will Mix With R12 But I Have Heard That It Will Not Cool As Well. Good Luck
You do not want to buy Freon as it is very, very, expensive. Have the leak repaired, the system purged of all Freon R12 and the oil. Have it converted over to R134 refrigerant. You cannot just add R134 as the oil used in R12 is not compatible with R134. You will be money ahead by converting it.
Check the ports to add freon--the low side is a large hose --the high pressure is the small line--on the large line if the valve is the large style----the freon is R134--if the valve is the small style it is R12--no longer used --retro valves are available to convert R12 systems to R134 R12 fittings can't be connected to R134 gauges, and vice versa. If it's R12 you won't be able to connect the hose from the supply can to fill it, or do anything else with R134 equipment.
Only if you're trying to destroy your AC system. Never mix refrigerants.
it uses R12 but it should be converted to R134
1994-1996 Depending on manufacturer.