Sorry to raise an old topic. Maybe this information will be useful to someone in the future.
I want to tell about my Hi-Lift Jack HL484 48″ Black Cast and Steel Jack. This is 48” cast iron and steel jack and is made up of four different component materials. All the parts are either cast or stamped steel.
This model is quite lightweight, coming in at only 28.9lbs, it delivers a very strong punch of performance.
Rated load capacity: 4,660lbs
Load capacity max: 7,000lbs (Tested)
This model comes with an easy to winch handle, durable mechanical operation, and a shear bolt, so if you decide to lift an M113 Bradley to change a tank tread, well it won’t let you. The mechanism is easy to operate, so I don’t sweat when applying this in any situation.
And one more model it's Torin Big Red 48″ like this
https://mechanicguides.com/best-farm-jacks/ which my brother bought recently. The Torin Big Red 48″ ratcheting off-road utility farm jack weighs in at only 30.1lbs and it can life 6,000lbs from 5.12” to 40”. So its an impressive piece of metal machinery.
This model conforms to ASME B30.1 standards, and it operates smoothly. It is used both vertically and horizontally and can be used for lifting, pulling, clamping, winching, and spreading.
The mechanism is really smooth, in fact, its one of the smoothest, we felt, so it competes with Hi-Lift.
It's one usefull video
https://www.youtube.com/watch?v=0KbEfqJJLWQ