A drive belt, whether dedicated or multi use serpentine type, may be loose or faulty. When the extra load of the AC is added, noises and slipping may occur.
A dirty or otherwise faulty AC clutch can make odd noises, as well.
Make sure they are right and get a real pressure test done.
A dirty or otherwise faulty AC clutch can make odd noises, as well.
Make sure they are right and get a real pressure test done.