Well apparently I dont want you working on the 100 I have owned. 5 AGM batteries that are under your NUTS, DO NOT add much ballast weight to the lifting of the machine, so yes if you put a lighter lithium pack in the lift, you could re-ballast the weight with rocks if you wanted. You obviously did not take physics and don't know basic math. I assure you I do. GAWD some of these replies are the dumbest things I have read in some time. Just FYI those batteries weigh a total of 350 lbs. And if you want me to draw you a diagram on leverage and show you how LITTLE effect 350lbs has on the LEVER of that machine when they are in the front 60% of the weight load I can take you back to school. Listen in math and learn, or just listen to some idiot on this site. I bought a hyster, so if I put an aluminum bottle on it instead of metal, do I lose all lifting capacity? Its MATH.