
644 P WHEEL LOADER
Mid-Size Wheel Loader
- Net Power: 186 kW (249 hp) at 1,800 rpm
- Operating Weight: 18 709–18 744 kg (41,246–41,324 lb.)
- Bucket Capacity: 3.1–3.6 m3 (4.0–4.75 cu. yd.)
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Features

Overview
SmartWeigh™ is a John Deere designed and supported payload weighing solution that delivers accurate measurements, dynamic weighing capabilities, and is easy to calibrate. For those not sold on whether or not a payload weighing solutions is a fit for your application, John Deere offers a low cost 250-hour trial period that provides you full SmartWeigh™ capabilities to help enable you to make the decision.
Benefits
- Leading Accuracy: SmartWeigh™ provides operators with increased accuracy (+/- 1.5 percent) because of John Deere’s expertise knowledge of our loader’s kinematic properties and exact dimensions and specifications. This ensures near exact target weights are hit and efficiently loaded into feed mixers, trucks, hoppers, or processing plants. This also helps prevent the loader from having to go back to the pile to get more material or to dump excess material.
- Seamless Calibration: Unlike other payload weighing systems, SmartWeigh™ does not need to be calibrated with a known weight and is designed to be easy to complete without the help of a dealer. By going through an easy-to-follow calibration process in the machine monitor, the system will be ready to accurately weigh material.
- Dynamic Weighing: There’s no need to constantly lower and reraise the boom of the loader to determine the weight after tipping off material. Bucket capture height can be set anywhere from 15-90 percent of boom height and can be captured at any boom speed. The SmartWeigh™ system can automatically determine the new weight after tip offs, reducing the time it takes to load the exact amount of material.
- John Deere Designed and Supported: SmartWeigh™ is a John Deere designed and supported solution meaning if issues arise, the only call you need to make is to your John Deere dealer.
- JDLink™ Integrated: Integration of payload weighing data into JDLink™ means that you can access the data from nearly anywhere, not just within the cab of the machine.
- Factory and Field Kit Options: A range of options are available to equip John Deere utility loaders with SmartWeigh™ including fully integrating from the factory or adding through field kits. The 250-hour trial period enables you to utilize SmartWeigh™ for 250 machine hours and decide if you would like to easily add on the feature for the life of the machine after the trial period expires.
*SmartWeigh is not legal for trade.


Overview
New P and X-Tier utility loaders will now be equipped with Auto Level that enables near perfect parallelism throughout the boom raise and lower cycle. In addition, enhanced performance buckets and Z-Bar linkage on P and X-Tier utility loaders are designed to enable loaders to be configured in a manner that allows them to be as productive as possible.
Benefits
- Auto Level can be enabled through the primary machine monitor and allows operators to set their desired attachment angle and keep that angle within +/- 2 degrees throughout the entire boom raise and lower cycle. This minimizes load rollback when using forks or buckets to improve load leveling
- Auto Level currently not available on machines configured with Tool Carrier linkage
- 8 degrees of parallelism is achieved when Auto Level is disabled
- High-Lift linkage adds an additional 304.8 mm (12 in.) of hinge pin height over standard linkage
- Cross tube and boom geometry design offers improved visibility to front attachments when operating and changing out between attachments during the day
- Bucket material retention has been improved by providing a 15 degree increase in bucket rollback to reduce material spillage Curved side cutters and integrated spill guards improve bucket fill rates




Overview
The redesigned cab in the John Deere utility loader lineup features improvements that provide the operator a first-class work environment with a range of creature comfort options to keep operators comfortable and productive no matter the task at hand.
Benefits
- An additional 76.2 mm (3 in.) of leg room has been added over the previous series loaders.
- Dual tilt steering column allows for dual tilt between the column and wheel to allow operators to customize the position of the steering wheel to their needs.
- Additional 12V accessory outlets have been strategically placed for proper powering of devices and a USB port has been added for connecting to the radio.
- Auxiliary accessory mounting points are strategically placed on the right front and rear cab posts for equipment such as a payload scale interface or CB radio.
- Upgraded heating, ventilation, and air conditioning (HVAC) system to improve cooling capacity, more precise control and increased reliability and durability.
- The AC unit has been relocated to the right side of the cab for easier access and service.
- The fresh air filter exchange is made through the top of the unit located outside the cab. This allows the dirty filter to be replaced completely outside of the operator compartment.
- Brushless motor provides infinite fan speeds, quieter operation, and increased airflow.
- Standard blower vent behind the seat for rear window defog that is adjustable to control direction of air flow.
- The sealed switch module has been updated and relocated on L-series and P-Tier loaders. The new location brings the switches to the operator’s line of sight during operation for quick reference and ease of selection and has updated and new functions included.
- Selecting the About button on the main menu of the monitor, then going down to sealed switch module (SSM) feature button the next screen takes you to a menu where you can view each button on the SSM and learn more about each feature.

Overview
Electrohydraulic (EH) controls allow for increased functionality to customize machine operations based on operator preference to increase productivity on a range of jobsite applications
Benefits
- Enable soft hydraulic stops to select how abrupt the bucket or boom stops when they reach the end of travel or when the lever of the joystick is released
- Personalize both multi-function buttons with up to 10 options selectable from the monitor including bucket vibrate that creates a slight vibrating action for precise control when dumping specific material or EH Precision Mode that allows for fine metering of bucket or boom movement
- Set and store up to 10 different attachment configuration settings including flow, responsiveness, and other modes through the monitor for the most frequently used attachments in your fleet

Overview
The Quad-Cool™ Cooling System on loaders is a John Deere exclusive that places the radiator, air-conditioner condenser, intercooler, and hydraulic, transmission, and axle coolers in a unique boxed configuration that is isolated from engine heat to cool these components more efficiently throughout the day.
Benefits
- The coolers are arranged in a manner that the operator has wide open access to both sides of them ensuring that all debris collected in the coolers can be cleaned out
- Cool-on-demand hydraulically driven variable speed fan is included with the speed of the fan being determined by the machine fluid temperatures resulting in better fuel economy and optimized cooling

Overview
With improvements to the electrical and hydraulic routing and features like ground level servicing and Quad-Cool, customers get an upgraded serviceability experience while building upon known features that they’ve come to expect from John Deere Wheel Loaders.
Benefits
- Wire harness routing has been enhanced and additional retention points have been added to reduce rubbing
- Elimination of at least 40 hydraulic leak points over previous series in addition to four less crossings at the articulation joint on a two-hydraulic function loader
- The pump manifold has been removed from the articulation area to simply ease of service.
- Controllers and fuse panel are all protected from the environment while also being more serviceable from inside the cab of the machine
- Ground-level daily service checks and fuel refill are conveniently grouped at ground level on the left side of the machine for easy access
- Quad Cool cooling system places coolers in a unique boxed configuration that’s isolated from the engine heat for increased efficiency and durability

Building on the advanced object detection technology offerings, SmartDetect is available on John Deere Utility and Production Class Loaders, as a field kit or factory install. This technology provides visual and audible alerts to the operator, to increase situational awareness of people or objects around the machine. There is also a distinct audible alarm to alert the bystander.
- Builds upon our operator centered Advanced Vision System by incorporating smart obstacle intelligence on the job site
- Featured on the in-cab display are projected path lines when in reverse; the in-cab display will also show the operator potential hazards in close proximity
- Alerts operator and bystander through distinct audible alarms
- Operator Alerts:
- Alerts operator of all objects behind the loader
- Provides unique audible and visual alerts when a bystander is detected
- Alerts triggered on speed-based zones
- Bystander Alerts:
- Provides a unique external alarm to warn bystanders when they are detected in close proximity
- Operator Alerts:
Option code 6525 is required for SmartDetect. The rear counterweight and wide hitch with pin is required for SmartDetect. Option Code: 6525. See image below.

SmartDetect Digital
Customers can view footage of near miss events captured through SmartDetect by subscribing to SmartDetect Digital, available in John Deere Operations Center web and mobile.
The digital footage captured consists of:
- Push notification alerts for near miss events (Received within ~30 minutes)
- Event based near miss report and corresponding video
- Weekly report of technology usage and event summary
- Event heat map summary for jobsite operation optimization and trend analysis

Specifications
DRIVELINE | 644-p-wheel-loader Current Model |
---|---|
Engine Manufacturer | John Deere |
Engine Model | PowerTech PSS 6068 |
Displacement, ltr (Inches³) | 6.8 (415) |
Rated Speed, rpm | 1800 |
Engine Output - Net, kW (hp) | 186 (249) |
Torque, Nm (lbf / ft) | 1100 (811) |
Transmission Type | Powershift |
Front Differential Type | Locking |
Rear Differential Type | Open |
Tire size - Standard | 23.5 R25 |
Service Brake - Type | Wet Disc |
Service Brake - Actuation | Hydraulic |
Parking Brake - Type | Wet Multi Disc |
DIMENSIONS | |
Wheelbase, mm (ft/in) | 3310 (10 ft 10 in) |
Height - Over Cab, mm (ft/in) | 3450 (11 ft 4 in) |
Ground clearance, mm (inches) | 386 (15.2) |
Width Over tires - Std, mm (ft/in) | 2875 (9 ft 5 in) |
Height - Pivot Pin, mm (ft/in) | 4090 (13 ft 5 in) |
Reach - At 2130mm 45° Dump, mm (ft/in) | 1610 (5 ft 3 in) |
CAPACITIES | |
Fuel Tank, ltr (gallons (US)) | 350 (92.6) |
Hydraulic Tank, ltr (gallons (US)) | 105.2 (27.8) |
Heaped Capacity, m³ (yd³) | 3.2 (4.25) |
Ride Control System | Optional |
Pump Type | Variable Displacement Axiel Piston Pump |
Pump Flow - 1, lt/min (gallons (US) / min) | 310 (82) |
System Pressure, bar (psi) | 251.66 (3650) |
WEIGHTS | |
Operating Weight, kg (lbs) | 18709 (41246) |