Setting new standards of power, performance, reliability and control
Challenger is the world’s most technically advanced tracked tractor. The new MT700 Series is built to the meet the rigorous standards required by the construction and agricultural industry, and are the only machines of their type designed and built exclusively for use as a tracked tractor.
The range comprises four new models from 235hp DIN to 306hp DIN:
Challenger MT700 Series
Model Engine Power (DIN)
MT735 235hp
MT745 255hp
MT755 290hp
MT765 306hp
The MT700 Series is built to a completely new design from the ground up, with every component made to uncompromising design and engineering standards. All feature:
- Outstanding performance from all new, six cylinder, 8.8 litre capacity Cat C-9 engines. Fully electronically controlled with a ‘full authority’ electronic engine management system. Engine and transmission linked by ‘Intellitronics’
- Cat-built all new 16/4 speed transmission, electro-hydraulically controlled, providing a top speed of 40kph plus a range of shifting options and automatic controls. Eight gears in the 8-15kph field working range. Uprated electronic over hydraulic differential steering system
- Redesigned Mobil-trac™ undercarriage with ‘Opti-Ride’ suspension and front axle pivot
- All new closed centre, load-sensing hydraulic system supplying 166 litres/min flow at 200 bar. Four standard (up to six) spool valves with electronically adjustable flow and pressure. Unique ‘Load Independent Flow Division’ system
- All new three-point linkage with a lift capacity of up to 11,758kg. Optional steerable hitch
- Unprecedented space, comfort and visibility from an all new cab. Tractor Management Centre (TMC) monitors and controls tractor functions. One-Touch headland management records two different, complete sequences. Surround-Flow ventilation system and air-suspended seat with 25 degrees of swivel to the right.
Unparalleled comfort and control
A purpose-designed, single spoke steering wheel with built-in ‘spinner ball’ typifies the attention to operator convenience that has gone into the design of the MT700 Series cab. Mounted on iso block suspension, the platform provides the ultimate working environment in terms of space, comfort and visibility. The air-suspension seat has 20 different adjustments and can swivel 25 degrees to the right.
Unsurpassed climate control for the operator is provided by the fully adjustable heating, ventilation and air conditioning system. Surround-Flow® ventilation supplies an industry leading 11.3 cu m/min airflow from a range of high and low vent positions. Operators have complete control of temperature, airflow and direction.
Optional Nightbreaker™ HID lighting provides as close to daylight as any lighting package can, with clear definition of detail from a greater distance than normal halogen lights.
The new cab is also equipped with the most sophisticated control technology. Heart of the system is the Tractor Management Control (TMC), which monitors and controls tractor functions. Mounted into an ergonomically designed console to the right of the operator’s seat, the TMC incorporates a monitor screen along with all the transmission, hydraulic, linkage and PTO controls. The TMC unit is equipped with elbow and arm rests – making the console an extension of the right arm.
A selector knob allows operators to set and adjust 16 different functions that are shown on the TMC display. These include settings for items such as transmission Power Management and spool valves as well as a performance monitor, and information about fuel use, tractor information and servicing. In normal operation the ‘Summary Screen’ is displayed and this shows forward speed, track slip %, engine rpm, hydraulic flow setting for each spool, current gear and PTO status.
The tractor will operate entirely normally without using any other screen, but the TMC display also provides superb control and performance enhancing functions.
Just below the TMC display are five finger-operated hydraulic levers. These provide electronic control of flow to the spool valves, and are set by switching to the hydraulic function screens on the TMC display. Electronic control also allows timed stop and start functions.
To the right, the linkage control lever sets the working height and movement of the hitch. A yellow button on its side is used for a ‘quick enter’ function to override the set height.
A large yellow knob behind is the PTO switch. Pulling the knob and collar up engages the PTO while pushing it down disengages drive.
All the main functions on the TMC are deactivated by the flick of a ‘road lockout’ switch. This prevents inadvertent operation while travelling on the road.
To the left of the TMC is the thumb-operated throttle lever. Soft rubber coated, it is easy to use in its convenient location. A decelerator foot pedal can also be used to reduce engine speed to a level set by the operator anywhere between 1,200-2,100rpm. The default setting is 1,200rpm.
Just above the throttle is the transmission control lever that operates in forward, neutral, reverse and park positions. As a new safety feature, the tracks will not move when the steering wheel is turned with the transmission in park. The machine will turn on the spot when the steering wheel is turned with the transmission in neutral. The top two buttons on the left of the lever are used to upshift or downshift through the gears. The bottom button, set slightly back engages the Power Management System (see transmission section).
One-Touch Management System
A single switch conveniently located just above the transmission lever, and easily operated with the index finger of the right hand, controls the One-Touch® Management System.
This supremely practical headland management feature allows operators to record entire headland turn cycles including functions such as changing engine rpm, gear shifting, raise/lower implement, PTO engagement, spool valve operation, etc. The switch has two positions – one for entering work (Work) and the other to the lift the implement at the other end (Raise).
One-Touch™ records the sequence while the operator is actually operating each function. Pressing the switch at the end of the bout once will start the raise sequence, and pressing it to its other position will automatically return the implement to work. The PTO has to be engaged manually for safety reasons.
The analogue dashboard is in perfect line of site. It uses standard instruments to monitor engine rpm, fuel level, oil pressure and hydraulic and coolant temperature. Warning lights are fitted in an arc above the gauges. The choice of guages resulted from customer research which showed a marked preference for analogue dials.
All new Cat C-9 engines
Challenger MT700 Series tractors are powered by the all new 8.8 litre, six cylinder Caterpillar C-9 engine. All engines are turbo-charged and intercooled. The 306hp DIN, MT765 model also has a waste-gated turbo.
The engine block is forged in Caterpillar’s own foundry, ensuring 100% in-house quality control. It is fitted with cast iron wet liners with a plateau-honed surface and mid support, which allow for a higher top ring position, resultiing in better cooling, improving fuel consumption and emissions. The design also makes the engine easier to rebuild.
The ‘crossflow’ cylinder head features four valves per cylinder for excellent airflow. The design means a vertical injector can be centrally mounted for improved fuel spray patterns - a significant factor in reducing exhaust emissions.
The ADEM III (Advanced Diesel Engine Management) system provides full electronic control and operates with ‘full authority’ to produce optimum performance with minimum fuel consumption and low emissions.
The C-9 is the first engine to use the new HEUI-B (Hydraulically actuated Electronically controlled Unit Injector) fuel injector. Hydraulic oil, acting on a piston in the injector, raises the fuel to injection pressure. Electronic control of the flow and timing of the delivery rate allows the system to tailor fuel delivery to precisely match the engine’s load and speed operating conditions. This optimises performance across the whole working range.
Purpose-built transmission
Designed by Caterpillar from the ground up, solely for used on a tracked tractor, the Challenger powertrain is the backbone of the machine. It is iso mounted in the chassis and supports the front frame rails, cab, fuel tanks, hardbar, hydraulics, linkage and drawbar. Caterpillar has filed 12 different patents for assembly that uses 13% fewer components than the previous Challenger 35-55 unit.
Full power is transmitted through each of the 16 forward, four reverse gears in the powershift transmission. There are nine individual clutch packs – seven rotating, and two stationary, and it uses just two clutches to transfer each gear. This improves efficiency compared with the more usual use of three clutches in other transmissions. There are eight gears in the 6-15kph field working range.
The engine and transmission are linked electronically via the Intellitronics® system that controls the shifting in relation to operating conditions. The system also provides a wide range of operating modes:
Shuttle shifting: Forward/reverse direction changes are made without using the clutch. Programmable shifting allows the operator to select the gears that will be engaged when the shift is made.
Skip shifting: Allows operators to jump through gears
Continuous shifting: Holding the up- or downshift button in forward or reverse provides smooth shifts through the gears
Sequential (Pulse) shifting: Simply pressing the up- or downshift button once results in a single gear change
Pre-select shifting: Allows operators to select the desired start gear before engaging the transmission (maximum 10th). This allows the tractor to start under load and automatically change down if there is too much slip.
Speed matching: The transmission shifts to the gear that most closely matches ground speed. This operates only at speeds more than 16kph, and is activated when the inching clutch is pressed and then engaged. This is useful when slowing down on the road.
Power Management
Further control sophistication comes from the ‘Power Management System’ which varies the engine, transmission and hitch settings to enhance tractor performance in particular applications:
Maximum output: Optimum output is achieved by monitoring engine load and speed. The system will change gears and throttle settings automatically to maintain maximum possible ground speed.
Constant engine speed: For use in PTO applications. Constant engine speed is provided without changing gears and maximises fuel efficiency.
Constant ground speed: For use with light load applications, the system alters engine rpm and changes gears to match any variations in load.
Unique Mobil-trac™ undercarriage
The now legendary Mobil-trac® system has been completely updated for the MT700 Series. The system combines the speed, mobility and versatility of rubber tyres with the traction, flotation, smooth ride and low ground pressure of tracks. Caterpillar invented the rubber track concept and continues to design and manufacture all the key components in the patented Mobil-trac® system.
The Mobil-trac™ system is connected to the chassis via a 203mm diameter ‘hard bar’, now fitted with the exclusive Opti-Ride® suspension system. This uses Marsh Mellowâ springs to isolate the ‘hard bar’ from the frame, not only providing suspension but also allowing the front axle to tilt at an eight degree angle allowing each track unit to independently raise up to 150mm above the centre.
The three mid wheels in each track now also feature suspension. The front two wheels pivot around a fixed point while the third is mounted on rubber block suspension.
At 240cm between axles, the Mobil-trac® unit is the longest in the industry. This long wheelbase improves balance and traction while the long belts reduce compaction. The new tracks have a 10% to 14% larger contact area than before. The track tensioning system is similar to that used on the Challenger 35-55. A pre-set hydraulic cylinder, cushioned by a gas accumulator, pushes against a swing link attached to the track roller frame providing an unrivalled 71.1 kgn of belt tension (16000 lbs).
The patented differential steering system now provides even better control thanks to a new electronic over hydraulic system. This provides speed-sensitive steering and a quicker steering response that helps prevent ‘twitching’ on the road. The turning radius is still tiny – in fact the MT700s can turn in their own length in Neutral.
* Marsh Mellowâ spring is a registered trademark of the Firestone Industrial Products company.
Powerful and versatile hydraulics
A quick response to changing hydraulic needs is provided by the 166 litre/min closed centre, load-sensing hydraulic pump. This supplies oil only on demand and will destroke and reduce flow when not required – conserving power.
Four spool valves are standard but up to six can be supplied – all numbered and fitted in stack at the back of the machine. Levers allow connections to be made under pressure.
A unique ‘Load Independent Flow Division’ system evenly divides the flow to the services in proportion to their specific demands. All the spool valves are still able to operate when there is a high flow demand on the system, rather than the highest requirement taking priority.
A three point linkage is fitted as standard in Europe. Lift capacity is up to
11,758 kg and there will be the option of fitting a steerable linkage. The PTO has torque-sensed, modulated engagement and braking and connects via a 20-spline, 1¾” diameter shaft.
Electronic control
MT700 Series uses three separate CAN-BUS systems to monitor and control the entire tractor. These link the various components to provide the performance enhancing automatic functions.
The first level is CAT-Bas the dedicated, hard wire system that allows key components to communicate with each other. Level two is the ‘Intellitronics’ CAN-BUS through which the operator settings are communicated to the tractor.
Working in combination with the first two systems is a third BUS system, built to the new ISO 11783 standard, that links the tractor to the implements and other ancillary equipment. This allows the simple ‘plug and play’ addition of Auto-guidance, GPS, telemetry communication and other systems. There is no need to break into the wiring loom. All the connections are already there.
Power-Pack accessory power outlets in the lower right hand side of the cab supplies all the standard connections, a strip of terminals and also Ag-standard plugs that have power whenever the ignition key is in the Run position. Cables to control boxes are routed out of the cab though a sealed access hole at the bottom of the rear window frame. A large bracket by the right window provides the space for mounting a wide range of units.
Service and Maintenance
Challenger tractors are renowned for their tough construction and reliability resulting in an enviable residual value. Ease of maintenance is designed to minimise downtime.
Daily maintenance checks on the new MT700 Series are all easily accessible. Engine oil level is checked with a dipstick and other oil levels are inspected with sight gauges. An enormous, lockable fuel filler is located under a small cover and is easily reached from the access platform.
The one-piece bonnet lifts with the aid of gas struts, and the radiators all fold away on hinges for cleaning. The batteries are located in front of the radiators. All the various filters are mounted in the vertical position and easily reached for simple, clean changes.
Challenger Dealers offer unparalleled levels of service and back up, providing 24hr a day, seven day a week support in the Challenger working seasons. An unrivalled parts back-up is provided by AGCO’s Parts Distribution network. This service is unmatched by any other farm machinery supplier.
