1972 Suburban AC unit refrigerant capacity

[KFF 1]

My 72 Suburban has factory front and rear ac which I'm planning on converting from R12 to 134a. Does anyone have any info on how much refrigerant and oil the system requires in order for me to figure out 80% of the R12 value ... Any help would be greatly appreciated

[Dave]

Originally Posted by KFF 1

My 72 Suburban has factory front and rear ac which I'm planning on converting from R12 to 134a. Does anyone have any info on how much refrigerant and oil the system requires in order for me to figure out 80% of the R12 value ... Any help would be greatly appreciated

Not sure if you have the original compressor, there's a label on it stating the system lbs of R12. Which I think is at least 4lbs to 4.25lbs with rear air. Not a 100% on this going from memory. Classic Auto Air probably has the conversion table from R12 to 134A