What type of refrigerant is used in a 1996 buick regal?

1996 Buick Regals most likely used R-134a refrigerant. While R-12 was common in older vehicles, by 1996, the phaseout of R-12 was well underway, and R-134a had largely become the standard in new car production. However, to be absolutely certain, you should check the sticker on your car's AC system, usually located under the hood.