Axle, front, 1500 Series MFWD for single or dual usage
The 1500 Series axle is available on all 8R Series Tractor models.  The heavy-duty design of components and structure make it possible to use this axle at any power level and with or without front duals.
1500 Series mechanical front axle
 
Feature 1500 Series
Hyd diff lock Yes
Limited slip No
Suspension No
Tire ratio / steps allowed 4 or 5
Duals Yes
Tread spacing Singles* 1574 - 2184 mm
(62 - 86 in.)
Tread spacing Singles 1524 - 2235 mm
(60 - 88 in.)
Tread spacing Singles w/Duals 1524 - 2235 mm
(60 - 88 in.)
Duals 2946 - 3658 mm
(116 - 144 in.)
Top speed 42km/h
(26 mph)
* Based on wheel equipment shipped to some geographic regions.
 
The 1500 Series axle uses a drop-box design gear case, which contains two drive gears, to transfer power to the differential from the output shaft of the transmission.
Axle structure

Axle structure

  • The drop-box design gear case eliminates the need for a driveshaft with universal joints and large shields.
  • The driveline is high for additional clearance under the tractor for crops or obstructions.
  • The drop-box design also makes it possible to change gear ratios to match requirements for expanded tire options.
 To reduce road lope in transport applications, a tight-fit hole and slotted hole are utilized on the MFWD disk-to-axle and disk-to-rim components to help center the wheel.  The tight-fit hole is 180 degrees from the slotted hole and is only 0.3 mm larger than the bolt.  It is important to place the bolt through the tight-fit holes first in order to center the disk properly.
 
The waffle-clamp design of the front wheel assembly is adjustable to fit a wide selection of row widths and evenly distributes stresses placed on the wheel for longer life.  The disk offset provides a true 1524-mm (60-in.) tread spacing for working in 762-mm (30-in.) rows.
 
Serviceability and reliability
 
The 1500 Series MFWD axle is reliable, robust and durable.  It has a high capacity wet clutch splined to the transmission output shaft consisting of one large Belleville spring, six separator plates and six friction disks, providing excellent torque transfer.
  • A one-piece axle shaft eliminates yoke deflection.
  • Expanding heavy-duty U-joint seals with anti-wrap slingers prevent seal damage from crops or twine for extended life.
  • Tow eyes are on the front of the axle for easy access.
  • A simple steering stop arrangement offers adjustability for fine-tuning in any row spacing.  Quick and easy to adjust by simply loosening one lock nut and rotating the screw to the desired position.
  • Increased load carrying capacity over a standard MFWD axle.
  • 50 percent more steering capacity than standard MFWD axle.
  • Differential lock
  • Dual capable
Chain location

Chain location

Steering stop

Steering stop

Steering capacity
 
Large steering cylinders provide capacity

Large steering cylinders provide capacity

Steering high-horsepower, large row-crop tractors with duals requires significant steering force.  The 1500 Series axle steering system provides increased steering force of up to 50 percent over the 1300 Series axle design, which is only approved for single front tires.
AutoTrac™ sensor
 
AutoTrac™ steering sensor location

AutoTrac™ steering sensor location

The wheel angle sensor, figure A, is located on the upper-left-side king pin.
 
Turn radius and axle oscillation:
 
Combining the modular design frame with a 3 degree caster angle and an adjustable steering angle, as tight as 48 degrees, allows tight turn angles even at narrow tread settings.
 
The high-pivot-point axle mounting allows the axle to oscillate a full 9 degrees before contacting the axle stops.
 
Dual tire row spacing from 559 mm – 914 mm (22 – 36 in.)
 
The 1500 Series axle provides the flexibility of singles or duals to match most applications.  This is accomplished with a heavy-duty structural design for added strength while offering significant increases in steering capacity.
  • Industry-leading 3658-mm (144-in.) center-to-center outside front dual tread spacing.
  • The axle structure provides the strength to carry high-horsepower tractor weight over the most challenging ground conditions.
  • 3658-mm (144-in.) row spacing will get tires in the center of rows as wide as 914 mm (36 in.).
Front dual tires provide:
  • Ultimate flotation and compaction management
  • Increased load-carrying capacity
  • Easy installation or removal. No need to remove inner tire.
  • Bolt-on components vs. studded flanges for superior flexibility for dual/no dual applications.
  • Narrow hub extensions ensure superior crop clearance for row crop applications.
Dual hub extensions
 
Narrow diameter extension and hub attachment

Narrow diameter extension and hub attachment

Power hop management
 
John Deere has led the industry in power hop research, power hop management, and ballasting for power hop control.  John Deere has demonstrated that power hop on rigid-beam-axle tractors can be managed through proper tire selection, tire pressure, and front-to-rear weight splits.
 
Soil conditions and increases in power levels impact, individually and/or collectively, levels of power hop management.  Refer to the optimizing performance in the wheel ballast section story for ballast and tire selection criteria that minimize the effects different soil types can impose on MFWD tractors.
 
Hitch application
 
In hitch applications, it is important to maintain at least 50 percent of the ballasted front axle weight (with implement raised) for steering control. Referring to the example below, the max ballasted weight of the front axle is 7756 kg (17,100 lb). If the tractor has a hitch mounted implement, when you weigh the tractor, with the hitch and implement fully raised, the front weight must be at least 3878 kg (8550 lb). Therefore, front axle capacity is directly proportional to the weight that can be carried on the hitch.
 
The MFWD axle has a front-weight carrying capacity equal to the front tire-carrying capacity.  For example, in row-crop applications using the popular 480/70R34 (155 load index) front tires, the highest load rating is 3878 kg (8550 lb) per tire.  Total at maximum pressure it is 7756 kg (17100 lb).  This means (depending on tire pressure and speed) there is as much as 3878 kg (8550 lb) available for support of rear implements in transport.
 
Maximum load carrying capacity of the axle is determined by the load carrying capacity of the tires and whether the tractor is equipped with singles or duals.
 
Tire compatibility
 

The 1500 Series axle is compatible with all Group 43 and Group 44 (A rated) front tire options.
 
* NOTE: Tractors equipped with Cat 4N/3 rear hitch require group 48 rear tires.
** NOTE: Group 44 tire tread spacing / wheel setting positions available are not consistent with normal row crop usage. Turn radius will be greater due to steering stop adjustment requirement.  See wheel and tire section for more information.

MFWD CommandARM™ controls
 
CommandARM controls

CommandARM controls

Shortcut keys on the CommandARM enable the operator to engage or disengage MFWD on-the-go, even under full load without stopping or clutching.  The switch can be placed in one of the following positions:
A. Auto
B. On
C. Off (brake assist)

Position A - Auto

MFWD is on but automatically disengages when either of the following conditions are met:

  • Either brake pedal is depressed and held to allow tighter turns
  • Transporting at speeds above approximately 19.0 km/h (11.8 mph) to reduce tire wear, will automatically engage when speed drops below 18.0 km/h (11.2 mph)
As with the brake assist position, when both brakes are depressed, the MFWD will automatically engage (if not already on) to provide four-wheel braking.
 
Position B - MFWD on
MFWD engaged continuously.
 
Position C MFWD off (Brake assist)
This is also referred to as the brake assist position.  Even though the MFWD is disengaged, when both brakes are pressed at speeds above 5 km/h (3 mph) the MFWD will engage to assist braking the tractor.
 
Additional equipment for use with 1500 Series MFWD axle:
  • 3M Front axle spacing kit:
         Front axle static weight for the 1500 Series MFWD axle shall not exceed
         6759 kg (14,900 lb) when using the 3M kit.
  • 843 Front Loader
          Refer to the material handling section of the Sales Manual.
Base Equipment On : 8295R
Optional Equipment On : 8225R, 8245R, 8270R, 8320R and 8345R
 
Last Updated : 08-Jun-2010