Particularly in the afternoons when it's hot, my AC sounds lke the compressor is trying to compress ball bearings when I turn it on. It puts out cold air and eventually quiets down but it sure is noisy on startup. Is this a sign of pending compressor failure? Down here we run car ac most of the year so it has had a lot of use since 1997.

 

you can have a shop throw an oil charge on it but generaly when they start making noise your on a short life span.