I've had two people work on the A/C, one that knew what they were doing, and one I'm not sure about. They say they can't find a leak. I'm suspecting it is in a line that is covered up, maybe where it goes through the cab. Anyway, I'm buying a case of Freon at a time, for 3.49 a can, and if I go through a case in a years time, it's still cheaper than having a shop to even look at it, let alone repair it. If I was planning on keeping the tractor, I'd go ahead and fix it, but we're planning on trading it if my son can ever find what he's looking for.