2017 rear suspension

Different shape to the front of the rails, front pivot point was raised an inch and front shock lengthened which gives it more front travel, the rail shape is supposed to help it get up on the snow faster. I did this to my 2014 and it seems to make a noticeable difference. Combined with the 2016 narrow front end it is a whole lot easier to ride side hill and in deep snow.

You need the rails, new front skid shock, front pivot and idler arm as they are all different.

Although I have not ridden a 2017 Mountain cat, I'm not 100% convinced you would need a new skid setup.

I added the dropped chain case, a belt drive and a 3" to my 2015 153". I went from feeling like a monkey trying to have his way with a football to a fairly decent rider once again. I left the rear skid alone and merely shaved down the rail tip caps a bit but, now I can control the sled and it rolls very smoothly like I always thought it should. It no longer reaches that point where it just seemed to want to tip over like it did before. I'm not saying the 2017-2018 skid geometry wouldn't be better but, the dropped chain case seemed to make a huge difference on my sled. In fact, I went from trying to figure out what sled was going to replace my Proclimb to actually loving riding it now.