Sounds like we have identical problems, except I have not replaced anything but the batteries at this point. How did you test the limit switches and where are they? I thought about replacing the joystick, but when I jacked up the drive wheels, the joystick worked fine, but didn't seem to have much power and that seems crazy as electric motors have a great deal of torque normally. My unit is a 1996 and from what I could find, they didn't come with the "Creep Mode", but it certainly acts likes that is what it is stuck in. I'm going to check out the motor controller and see if I can tell if that has been changed out, and if so the replacement might be newer with the "Creep Mode". One thing that is driving me crazy is the fact that the lower boom worked fine with the crappy batteries that were in the unit when I purchased it, but now, with new batteries it has worked sporadically, but now just tries to lift. I kept trying it and the lower hydraulic cylinder blew a seal, so I had it rebuilt, no leak now, but still won't lift. I actually wonder if the cylinder was bad before, but all of the lift pressure went to that cylinder and over pressured it, but I don't know. There is only one hydraulic pump, that switches from one function to another. The upper lift works great, the boom extension works fine, drive works on level ground with minimal power, but will not climb any grade at all and the lower boom will not work now. I don't understand!!