I am not sure what all the differances are but I know the shape of the back edge is differant on the 08. The top edge of the tailgate sticks out a little and is not rounded like years past. I have a snug top on my 08 and the modle I have is a new one. I gues before ( which you can still get if you want )it had 2 locks, one on each corner and the one I have has 1 lock in the middle. Also when you close it you just have to push it down and it will lock with out turning a key.