Was built for R12, can be converted to R134a.
R134A
R134a
R-134a
r-134
1994 Chevy lumina freon type
R134a
134 freon
There is only one Freon, and that is R12. R12 Freon came installed in your 1991 Chevy. It may or may not have been changed over to R134 Refrigerant. If not change it over, as the cost of R12 is unbelievably high an is no longer in production.
R134a
It does not matter on that year, just make sure that it is POWER STEERING FLUID.
Freon is R12. Your 1997 Chevy uses R134 Refrigerant.
R134a