Is it making any weird noises from the compressor when you engage it ? I would take the belt off and turn the compressor ON and try and turn it by hand ( wear gloves...) and see how it feels. If it feels rough or is locking up then yes, replace it. Just turn the key to ON and turn the AC on with the compressor energized to engage the AC clutch, then turn it by hand with the belt off. Do you see evidence of it leaking oil ?
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