It's only Freon if it was manufactured by DuPont, but to the important things... Your 89 would have had an R12 system from the factory. You can't use R134a in an R12 system unless you do at least a partial retrofit (evacuate all the R12 and compressor oil, replace the orifice tube, replace the accumulator, replace the hose connections, add PAG oil and R134a).
No, there is retrofitting required.
newer vehicles, such as a 99 jeep, all use 134-A refrigerant.
All cars manufactured after 1993 were required to use R134a refrigerant.
R134a . All vehicles after 94 went from R12 to R134a
Chevy switched from R12 to R134a for the model year 1994. Your truck should be R134a.
It uses R134a.It uses R134a.
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