2008 F250 6.4L issues with A/c
 

I have been having issues with my A/C not blowing cold air. When it first started it was intermitting and would not work for awhile then it would cut on, but now it will not cut on anymore. I have checked to see if the a/c is low but it dosent seem to give me an accurate reading. I believe it might be the clutch but not 100% sure. Also when I turn on the a/c then turn it off it starts to squeal not sure if it is the clutch or just a bearing.