The John Deere 444D wheel loader is a rugged, mid-size machine designed for efficiency and durability in material handling and construction tasks. It features a naturally aspirated 6-cylinder 5.9L engine delivering 97 gross horsepower (90 net hp) at 2400 rpm with peak torque at 1300 rpm. The loader’s operating weight is approximately 19,220 lbs (8,718 kg), supported by a 7.9 ft (2 m) wheelbase and 15.5-25 tires, providing stability and traction. Its power shift planetary transmission offers 4 forward and 2 reverse speeds, reaching a maximum forward speed of 24.6 mph (39 kph) and reverse up to 8.8 mph (13 kph). The hydraulic system includes a gear-type pump delivering 40.8 gal/min (151 l/min) with a relief valve setting of 2250 psi, enabling bucket dump, raise, and lower cycles in 1.5, 5.9, and 3.6 seconds respectively. The loader’s bucket has a heaped capacity of 1.5 cubic yards (1 m³) and a breakout force of 17,000 lbs (7,711 kg), with a width of 7.4 ft (2 m) and a maximum dump clearance of 9.2 ft (3 m) when fully raised. Key dimensions include a height to top of the cab of 10 ft (3 m), hinge pin height of 11.4 ft (3 m), and a total length with the bucket on the ground of 19.3 ft (6 m). The machine operates on a 12-volt electrical system supported by a 65-amp alternator. Hydraulic fluid capacity is 16.2 gallons (61 liters), and the fuel tank holds 50 gallons (189 liters). The rear axle oscillates 22 degrees, enhancing off-road maneuverability with a turning radius of 13.9 ft (4 m).