I have the 2014 Arctic Cat wildcat 4 x limited. I heard what sound like bearings grinding rocks, was coming from the 2 pillow bearing assemblies for the front wheel drive shaft. I pulled everything out and opened up the tunnel and replaced both bearing with new bearing and added new grease where they spline together. I noticed a o-ring on the ends and they look ok. I put it on the lift so I was able to put it in gear with the tires just off the ground and it seemed like the noise went away. After getting it all back together and went for a ride it sounds worse now then ever. Now it sounds like its coming from the rear where it was coming from the front seat tunnel area.