Last year my mechanic replaced everything on my a/c unit on my 1988 chevy silverado. Vacuumed out the old freon ..... . Worked great for two months but seldom used. After that it stopped working. It blew warm air. I thought maybe there was a leak but when I tried to add freon the gage said full and the a/c clutch was running. Usually the a/c clutch will come on after you put enough freon in it. Also all the a/c hoses were very hot to touch. So not sure what to do at this point. A/c clutch is on but no cold air. Text my mechanic a few times. He told me that system just leaks and there is nothing to do about it. After that he quit texting back.