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Get a high pressue gauge (Northern Tool has a 0-5000# for $10). Put it in your high pressure line and measure the pressure with the tractor at PTO speed. Put the hydraulics back like they were. Measure the internal diameter of your cylinder (piston width across the top) and divide by 2. Take this number x the same number x 3.14. Multiply this by the pressure you measured and you have your lift capacity at the cylinder. Any lift arm length will either add to this or subtract depending on whether or not you have distance between the cylinder and what you want to lift. So for a 1200 lb measurement of pressure, and a 3" cylinder we have 3"/2 = 1.5" x 1.5" x 3.14 x 1200 psig = 8482 lbs lifting capacity according to my calculator. If the lift arm pivots at the tractor and the cylinder is 1 ft from the tractor and the length of the arm (at the point where you are lifting) is 3' from the tractor then you have a second class (as I recall) lever gain of 3' - 1 ' = 2 ft so lbs x ft = 8482 x 2 (feet x pounds....ft-lbs)or 16,964 lbs lifting capability. Now with that said, the practical side of all this is hydraulic leaks, piston blow-by and ability of your tractor to support that kind of load. Probably a couple of thousand pounds is more practical. Awesome isn't it, what hydraulics do for us every day in every walk of life. Mark
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