I have a cat e5000 I bought 10 months ago used. The unit has only 2600 hrs and it was sold to me with a 80% used battery. When we first recieved the forklift it would shutter or jerk seldom. Now the machine will hardly move without jerking then shutting down. When moving it is like you jam the brake then immediately release it. After a while of this the machine will creep very slowly then not move at all or suddenly leap into motion. Of coarse the tech told us the battery was shot so we purchased a new battery last week but still have the same problem. When reviewing the maintenance history of the machine since new this appears to be a reoccurring problem.