I have a 1999 Chevrolet Suburban 1500. The air stopped working. I found a leak at the accumulator and a very small bubble at the shreader valve and replaced both. After I recharged 3lbs into the system and dye tested at that time and had no visual leaks. Follow day truck was blowing warm air. I hook up my AC machine and truck only had a 1/2lb of freon. Ran a vacume test and it held vacume. Recharged again with 3lbs of Freon with dye and rechecked for leaks in front and rear and no signs of any visual leaks or it being wet. The next day truck blowing warm again and no visual sign of any leaks anywhere. Used the dye light and then the sniffer and again no leaks found. Hooked up adapter up to shop air supply and ran 100lbs of pressure to the system and while hooked up the system held pressure for 8 hours at 100lbs. I disconnected the shop air at the end of the day. The following morning the system was low by 25lbs. Still no visual leaks and negative on the sniffer test or dye light. Where the heck did 6lbs of freon and 4oz's of PAG oil go? I am stumped beyond belief. Any suggestions on next steps?

Help,

Frustrated Tech

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