I noticed my ac in my car wasn't working to it's normal potential, as I was driving on the highway with the cruise control on I noticed my car bucking. After some investigation we (me and my friends, they are mechanics) noticed that there was metal debris all over my engine coming from the ac compressor and the clutch was engaging and disengaging while making a horrible whining noise. The bearings in the clutch have burnt out. I bought a used ac compressor with warranty from ebay. It cost me $90 with shipping. As a new one cost about $400, the most expensive part of this is going to be recharging the unit. Unless you know someone who can do it for you cheap. I am currently waiting for the part to arrive in the mail and will be installing myself as it is much cheaper, and well I can actually do it. This seems to be a common thing with subaru.