I have a 2003 Grizzly with just over 2000 miles on it. At times when letting off the gas I hear a clicking noise which sounds like it originates from the transmission or rear gear case. Today while riding 2 up on a rough trail it felt like the transmission was slipping or not pulling on all the wheels. Just 100 yards from home it click clicked and quit all forward movement. Towed it home with our UTV in Neutral, thought we tore out the rear diff. Quickly checked out the drive shaft and rear diff and everything appeared ok. Son jumped on it started it up, and drove off in 2 wheel drive just like nothing was wrong. Something is up, and recommendations would be greatly appreciated.