Years ago my company installed a 4 post heavy duty electric lift where I worked as an in-house tech. It was manufactured by Rotary and they have them on their web site, up to 60,000#. We also had what they called a bridge lift accessory that ran on rails between the ramps and also had an air operated pancake jack on it. Worked very well. It is so nice to be able to stand up under a lift truck while servicing it. Later, I worked at a large dealer that also had a similar lift. They are out there.