2016 S590 with aprox 1700 hrs. When I bought the machine it sounded like the tens arm for the drive belt would chatter. when you looked in there the arm was definitely jumping around a little and making lots of noise more so at idle. So I get a new belt, tens arm and pulley. Its an updated arm that has a weight on it in addition to the idler wheel. The old one had a weight as well that was round and about the size of the idler pulley. the new weight is bolted on with two bolts and and is about 3/4 of a circle and is right beside the idler. I install everything last night. The new belt seems to sit quite high in the pulleys compared to the old with 1700 hours. Put 40 ft/lbs on the tens and tighten it all up. It still makes a more noise then i like. Its more of a squeal/chirp now versus more of a chatter of a loose tens arm before. You would swear the alternator has a bad bearing or something, but its the new pulley on the belt. The belt between the engine pulley and the tens pulley still jumps up and down a fair bit. If i spray just a little water on the back side of the belt it goes nice and quiet but as soon as the water dissipates it chirps again. its worse at idle but i think i can still hear it at high rpm and also a bit worse when under a bit of a load. I was never loosing hydro press or any thing, just hate the noise that its making. I looked at a couple of other bobcats n those belts run smooth as butter. mine chirps away and the tens arm is jumping around. Not a lot but probably an 1/8 of an inch, not smooth like the others. I tried 50 and 60 ft/lbs as well as just letting it run on just spring tens with all the same results. Any one have any ideas for me to get it to run smooth?