All the work is being done by a reputable mechanic but I think he is perplexed on this problem. He has a 4 bay garage with several mechanics working there so i'm sure he has all the equipment for the job.
I have a 2003 GMC Sierra 2500 Duramax that keeps blowing out the Freon from the AC Compressor. I have replaced the compressor 3 times, fan clutch and condenser but it keeps building up too much pressure. What else could be causing problem?