John Deere produced its 840 farm tractor model From 1976 Until 1986 in United states with a Four-post ROPS cabin. Talking dimensions and weight, this model weighs 5004 lbs or 2269 kg has 65.4 inches [166 cm] of width, 138 inches [350 cm] of length and 94.1 inches [239 cm] of height while maintaining a wheelbase of 74.4 inches [188 cm] the front tread is about 49.6 to 79.5 inches while the rear tread is 53.5 to 73.2 inches . This tractor can fit ag tires of 6.50-16 front and 6.50-16 back . This John Deere 840 is powerd by a diesel engine it has 179 ci or 2.9 L 3 cylinders ,it can produce 37.5 hp or 28.0 kW at 2400 (rpm), the fuel tank capacity is 20.6 gal or 78.0 L. This machine has 4x2 2WD wheel drive system,16 forward and 8 reverse transmission system.