It is rare for the Awd to grab while in 2wd. In rare conditions like maybe on ice or on a lift sometimes when you get the rear wheels spinning at about 45-50 mph it can try and snap in. In MOST cases as long as the front wheels were moving at some speed (it doesn't have to be alot) the front wheels would not engage. On the other hand, if you do alot of wheelies or jumping with the AWD turned on you can cause this to happen. The propshaft can twist itself out of index and cause a vibration that can cause unwanted engagement. For those that don't know, The AWD doesn't engage until the rear wheels slip. If you have it turned on and go and jump off a ramp or hill or whatever you can get air on when you leave the ground the rear wheels increase dramaticly in speed and since they are spinning faster than the front wheels, the awd engages and it slams in really hard to catch the front wheels up with the rear. When this happens it puts way more stress on the propshaft than under normal engagements and it will overtime twist itself out of index. The yokes change there alignments and this causes the engagement issue. So if you keep it in 2wd unless you need it may help reduce the possibility of this happening. This has caused the unwanted engagement in all but one and it was a warped front driveshaft. Oh, and don't say you don't play like that in 4WD, we all do. Maybe we forget its on or just not think about it. But I bet you will now. The AWD setup on the Polaris is simple. So simple it can give you a headache when there is a problem.