BAM! Backed my 2011 4 off the trailer, put it in drive, moved it forward next to my truck and when it was coming to a stop, it grinded a little bit then BAM! Rear differential got a hole punched out of it from the inside. WTF? Thank God for the Polaris extended warranty. All I do is tight trail riding so its not been raced or had the holy hell beat out of it. Taking it to midwest powersports tomorrow and dropping her off.