The refrigerant used in a Chevy S-10's air conditioning system depends on the
year of the truck. Older S-10s likely used
R-12 (Freon-12), which is now banned due to its ozone-depleting properties. Later models almost certainly use
R-134a, a more environmentally friendly refrigerant.
To know for sure, you need to check the sticker on the underside of the hood, the owner's manual, or consult a repair shop with access to vehicle information databases.
