no my friend this is not only caused by chinese gas
sometimes the bearings inside the compressor give up and break and sometimes the shaft itself goes and sometimes the pistons or the rotors scrap and make those magical powder which then kills the performance....
and i am replacing almost the complete system only the pipes and evaporator if not leak will be reused other things like the compressor condenser and the valve will be changed
Well a jammed compressor is a different story altogether. And overhaul is different and cheaper than a complete replacement of the entire system. And Ive seen this before also, usually because of cheap chinese gas which was hitting the market and one time. Jamming compressors left and right.
bhai mustang and blazers have orifice system a/c even with the condenser at its full capacity and compressor at its optimum pressure will come to 3 to -2c in the tvx system
and for that type of cooling you might have to put aditional heat exchanger at rear and toss in a additional condensor at front so the cabin temp will drop further down as the these are duct temp and cabin temperature further varies at 10 to 15c