I spun both by hand (and every pulley actually) and none made sound at the speed I was able to spin them... I did replace all of my AC system BUT the compressor (and I think they say you should replace compressor when you replace the system but I didn't replace my system because it went bad I did because I ended up ruining my condenser ripping out my radiator lol so I then replaced the dryer, condenser, and orifice filter all together. AC still has not been filled (and has remained off at all times). Is there a good way to narrow sound down more effectively? Maybe a doctor scope thing? Lol.