Mine is a 2011 model. I am told the RZT's have a similar drive system. I am trying to figure out how much I am being jerked around. The dealer has disabled the rod that causes the tension to go slack in the transmission drive belt. They say they have done this now on several RZT's. They also said that until about two years ago activating the brake did not cause the transmission belt to go slack. They siad that all of the commercial model mowers maintain tension in the hydro drive belt all the time. My concern is with the hand brake set if you put your foot on the forward or reverse pedal you can hear the hydro's strain. They insist that the rod is locked and there is only a slight amount of movement that causes the straining sound. I have not gotten underneath the mower to study the rods to confirm this. If this info is incorrect and someone got on the mower with the hand brake set and pushed the forward pedal all the way down what damage would occur. The dealer says a Cub Rep is suppossed to be in next week and they will contact me so that I can bring the mower out and talk to them. If that doesn't happen I will probably go ahead and contact Cub direct. The shame of this is that 4 times I have had to use my 27 year old John Deere 420 to go and retrieve the mower from the bottom of my yard. Most of my neighbors have seen this. Not good advertisement for Cub.