As some of you may remember I have had extensive work done on my climate control system. I have spent near 4K on this to date. The car is back in the shop because the last R-12 charge did not last more than a few days. This would be the third charge. I have asked the service manger repeatedly for him to put dye in the system. Each time he has said that he fixed the leak and dye is not necessary. He is now stating that the dye he has only works with 134 and that I need to convert to that. Is there any truth in his claim about the dye? BTW the charge for the retrofit is 78.00 that seem reasonable?