Folks I have a 2007 B7610 HST with a 54" belly mower and a loader and 250 hrs on it. Bought it in June from a dealer who claimed it was like new and given the outward appearance and its operation on a flat parking lot I had no reason to doubt him. I got it home and started mowing on my very hilly lot and noticed that sometimes when I start up or down a hill at a very slow speed the tractor will jerk momentarily like the transmission just engaged a lower gear. There is no slippage or change in the sound and no other indication that there is anything wrong. The transmission fluid level shows full on the dipstick with the tractor off. The question(s)... Is this something common to these tractors or if it's not a common problem what would some of the likely causes be that I could check out before taking it to a dealer. I'm obviously a new owner and would appreciate any advice.