tranny hesitating

the fact that your trannys are hesittating is a drivability problem to begin with and is sign that your trany is going out....as for what it is it could be a number of things from the lack of changing the fluid and filter or damage to the hard parts themselves
one common and posiblity is the overdrive one way clutch if its hesitating to gointo drive or the reverse oneway clutch if hesitating to go into revers..... as for cluncing pop the hood and have some one watch the engine it it moves more than half an inch whene placed into iether drive or revers with the engine running you probably have motor mounts or tranny mounts that have gone bad and as they may not couse driveabillity problems the will couse other things to be in a bind such as cv gionts and your rack and pinion steering and not to mention the engine and tranny wireing ... do not let them just go becouse the car still drive it will cost a lot more down the road.............