Independent-Link Suspension utilizes industry-leading technology
8R Series Tractor equipped with ILS

8R Series Tractor equipped with ILS

The John Deere Independent-Link Suspension (ILS™) utilizes industry-leading technology to supply unsurpassed gains to end-user productivity. This innovative design incorporates proven suspension design with mechanical front-wheel drive (MFWD) axle components that use state-of-the-art technology specifically for heavy equipment usage.
 
The ILS front axle is available on all 8R Series Tractor models.
42-km/h (26-mph) and 50 km/h (31-mph) front axles
 
Feature  
Hydraulic differential lock Yes
Limited slip No
Suspension Yes
Brakes Yes (optional on 42 km/h)
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.)
Singles with duals 1524 - 2235 mm
(60 - 88 in.)
Duals 2946 - 3658 mm
(116 - 144 in.)
Top speed 42 km/h (26 mph)
* Based on wheel equipment shipped to some geographic regions.
 
The ILS system gets more power to the ground because the front tires maintain ground contact pressure. This improves field and transport ride plus increases ballasting flexibility and drastically decreases the tendency to power hop.
ILS cutaway

ILS cutaway

The ILS axle maintains minimum oil levels in the front differentials to assist in providing overall tractor operating efficiency.
 
John Deere ILS has three systems:
  • A mechanical system
  • A hydraulic system
  • An electrical system
 
Mechanical system
 
The mechanical system is further broken down into the mechanical drive system and mechanical suspension system.
The mechanical drive system includes:
  • A three-position switch is included on a MFWD clutch.
  • The MFWD clutch has six clutch discs and separator plates that can transfer as much as 40 percent of the tractor power through to the front ILS axle.
  • The front differential transfers power from the engine to the individual right and left driveshafts through a ring and pinion.
  • A hydraulically engaged front differential lock containing eight clutch discs and eight separator plates works in conjunction with the rear differential lock to assist the tractor in tough, wet conditions with increased power transfer to all wheels.
  • A right and left constant-velocity telescoping driveline provides smooth power transfer to the outboard hubs.
The mechanical suspension system consists of large cast upper and lower control arms with cast steering knuckles for durability and reliability.
  • There is a high steering capacity, even with dual wheels.
  • High torque in all steering positions provides maximum transfer of power to the wheels under all conditions
  • Fully independent suspension maintains optimum ground contact at all times.
Hydraulic system
 
The hydraulic system consists of suspension cylinders, a control valve manifold, a front differential lock, and hydraulic accumulators.
  • There is a high steering capacity through large steering cylinders.
  • Responsive link arms maintain contact with the ground surface, giving maximum tractive performance under any condition.
  • Accumulators dampen energy from bumps to produce a smooth ride for maximum operator comfort.
Electrical system
 
The electrical system contains position sensors, solenoids for the control valves, and a master controller for complete automatic control of the ILS system.
 
How does it work?
 
The mechanical, hydraulic, and electrical systems work together to maintain a level and vertically centered position of the front differential case in relation to the outboard hubs and planetaries, independent of tractor weight or dynamic loading. The system's ability to maintain a vertically centered position provides full suspension travel of 25.4 cm (10 in.). This translates to consistent soil contact for improved power to the ground as well as dampens the energy from bumps that cause a rough ride.
 
The tractor utilizes electronic and computer controls that monitor tractor functions and axle position. Based on those inputs, the electrical system automatically triggers hydraulic functions to raise, lower, or remain static.
 
The John Deere Independent-Link Suspension uses a short/long A-arm design, which means the upper control arms are shorter than the lower control arms. During wheel movement, the upper control arm moves in a smaller arc than the lower control arm, and the difference in the two arcs creates a change in camber. The change in camber helps keep the inside and outside of the front tires perpendicular to the drive surface, a very important feature when optional front dual wheels are installed. This design provides anti-dive characteristics to naturally reduce the adverse effects of braking and acceleration.
 
The John Deere ILS front axle has been specifically designed to accommodate additional options, such as front 3-point hitches and front duals. To properly handle these options, large steering cylinders and knuckles provide up to twice the steering capacity of the standard MFWD beam axles so steering performance is maintained. A simple steering stop arrangement offers infinite adjustability for fine-tuning in any row spacing.
 
Braking system
 
With higher speeds and expected heavy towed implements and carts, front brakes (code 6061) are optional on 42-km/h (26-mph) ILS-equipped tractors and part of base equipment on 50-km/h (31-mph) ILS-equipped tractors. The braking system is applied proportionally between the front and rear axle brakes to effectively stop the tractor.  There are no operator adjustments or requirements to operate the additional braking system.
 
Tire compatibility for 50-km/h (31-mph) travel speeds
 
Faster travel speeds require B-speed-rated tires that provide high-speed capabilities. Tire selections that are compatible with order code 5051 have this rating.
Front duals
 
8R Series Tractor with front duals

8R Series Tractor with front duals

Narrow-diameter extension and hub attachment

Narrow-diameter extension and hub attachment

Front dual tires provide:
  • Ultimate flotation and compaction management
  • Increased load-carrying capacity
  • Easy installation or removal; no need to remove the inner tire
  • Bolt-on components vs. studded flanges for superior flexibility for dual/no dual applications.
  • Narrow hub extensions to ensure superior crop clearance for row crop applications
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 maximum 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. A total of 7756 kg (17,100 lb) at maximum tire pressure. 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.
 
Additional ILS features:
 
There is no on/off switch for ILS operation since the John Deere advanced electronic management system knows when to disengage ILS automatically. The electronic controller will activate a restricted mode of operation, when any of the following conditions are met:
  • Both brake pedals are pushed
  • The 3-point hitch raise/lower switch is activated
  • The tractor is placed in park
  • Wheel speed is less than 0.5 km/h (0.3 mph)
  • Tractor is correcting for an out-of-level condition
Based on the inputs received (speed, suspension displacement, braking and operator input to hitch and/or remote cylinders), the tractor determines when the system should be active or inactive, making operation simple and efficient.
MFWD CommandARM™ controls for ILS
 
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:

1. Auto
2. On
3. Off (brake assist)

Position 1 - 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; automatically engages when speed drops below 18.0 km/h (11.2 mph)
As with the brake-assist position, when both brakes are depressed, the MFWD automatically engages (if not already on) to provide four-wheel braking.
 
Position 2 - MFWD on

MFWD engages continuously.
 
Position 3 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 engages to assist braking the tractor.
 
Additional equipment for use with ILS axle
  • 3M front axle spacing kit:
    Front axle static weight for the ILS axle shall not exceed 6759 kg (14,900 lb)
    Using the 3M kit.
  • H480 Front Loader
    Refer to the material handling section for additional information.
 
Last Updated : 26-Sep-2011