I have a '89 GMC sierra 4 wheel 3/4 ton. Recently the compressor was replaced and the new compressor came with vague instructions. I can't find the amount of pag oil to add for the new compressor. Please help.

 

It should say on the top of the accumulator, but I think the entire system holds around 6 ounces. Did you completely evacuate the system?

 

Nowhere on the truck is there info on the amount of oil for the AC system. The system was changed to 134a and may have the wrong amount of oil. I don't want to guess on the amount. Does anyone have a 89 gmc truck with the amount stamped?