John Deere 644K Z-Bar Wheel Loader
 Wheel Loader // John Deere
                                John Deere 644K Z-Bar Bucket
                  | Breakout Force: | 33903 lbs (15,378 kg) | 
| Bucket Capacity - heaped: | 4.3 cu yds (3 m) | 
| Bucket Capacity - struck: | 3.7 cu yds (3 m) | 
| Bucket Width: | 10 ft (3 m) | 
John Deere 644K Z-Bar Dimensions
                  | Dump Clearance at Max Raise: | 9.4 ft (3 m) | 
| Ground Clearance: | 1.4 ft (0 m) | 
| Height - Top of Cab: | 11.1 ft (3 m) | 
| Hinge Pin - Max Height: | 13.4 ft (4 m) | 
| Length with Bucket on Ground: | 26.8 ft (8 m) | 
| Reach at Max Lift and Dump: | 3.7 ft (1 m) | 
| Wheelbase: | 10.7 ft (3 m) | 
| Width Over Tires: | 9.5 ft (3 m) | 
John Deere 644K Z-Bar Engine
                  | Aspiration: | Turbocharged charge air cooled | 
| Displacement: | 414 cu in (0 m) | 
| Engine Model: | 6068H, Tier III certified | 
| Net Power: | 232 hp (173 kw) | 
| Number of Cylinders: | 6.0 | 
| Power Measured @: | 1700 rpm | 
| Torque Measured @: | 1400 rpm | 
| Torque Rise: | 0.55 | 
John Deere 644K Z-Bar Hydraulic System
                  | Dump Time: | 1.4 sec | 
| Lower Time: | 3 sec | 
| Pump Flow Capacity: | 81.9 gal/min (310 l/min) | 
| Pump Type: | Variable axial piston | 
| Raise Time: | 5.5 sec | 
| Relief Valve Setting: | 3650 psi | 
John Deere 644K Z-Bar Operating Specifications
                  | Alternator Supplied Amperage: | 80 A | 
| Cooling System Fluid Capacity: | 7.8 gal (30 l) | 
| Engine Oil Fluid Capacity: | 6.5 gal (25 l) | 
| Front Axle/Diff Fluid Capacity: | 5.9 gal (22 l) | 
| Fuel Capacity: | 93 gal (352 l) | 
| Hydraulic System Fluid Capacity: | 29.1 gal (110 l) | 
| Operating Voltage: | 24 V V | 
| Operating Weight: | 40036 lbs (18,160 kg) | 
| Rated Bucket Capacity: | 4.25 cu yds (3 m) | 
| Rear Axle Oscillation: | 26 ° | 
| Rear Axle/Diff Fluid Capacity: | 5.9 gal (22 l) | 
| Static Tipping Weight: | 33576.5 lbs (15,230 kg) | 
| Tire Size: | 23.5 R25 | 
| Transmission Fluid Capacity: | 18.3 ft (6 m) | 
| Turning Radius: | 6.1 gal (23 l) | 
| Max Speed - Forward: | 18.3 ft (6 m) | 
John Deere 644K Z-Bar Transmission
                  | Max Speed - Reverse: | 22.8 mph (37 kph) | 
| Number of Forward Gears: | 15.5 mph (25 kph) | 
| Number of Reverse Gears: | 4.0 | 
| Transmission Type: | 3.0 | 
