| Manufacturer | Challenger |
| Price | - |
| Model | MT645 |
| Equipment Type | Row-Crop Tractors |
| Factory | Beauvais, France |
NEBRASKA TRACTOR TEST 1782C 2
| Description | Diesel 18-speed 4WD September 19 - 26, 2000 Link: Nebraska Tractor Test 1782C file PTO performance |
| Max power | 184.49hp / 137.6kW |
| Fuel use | 10.9gal/hour / 41.3l/hour |
| Power at rated engine speed | 181.26hp / 135.2kW |
| Power at rated PTO speed | 183.87hp / 137.1kW |
CHALLENGER MT645 POWER
| PTO (claimed) | 180hp / 134.2kW |
| PTO (tested) | 184.49hp / 137.6kW |
ENGINE DETAIL
The Challenger MT645 features a robust Sisu turbocharged, aftercooled diesel engine with a displacement of 7.4L, providing substantial torque for heavy-duty applications. Its dual paper air cleaner ensures efficient filtration, which is critical for maintaining performance and engine longevity, while the 16.5:1 compression ratio enables effective combustion for enhanced power output at a rated RPM of 2200. However, challenges include potential overheating in extreme conditions, necessitating effective cooling solutions to sustain operational efficiency.
| Description | Sisu/turbocharged aftercooled diesel 6-cylinder liquid-cooled vertical |
| Displacement | 449ci / 7.4L |
| Bore/Stroke | 4.251x5.278inches / 108x 134 mm |
| Air cleaner | dual paper elements |
| Compression | 16.5:1 |
| Rated RPM | 2200 |
| Starter volts | 12 |
CHALLENGER MT645 ENGINE
The Challenger MT645 features a robust Sisu 7.4L 6-cylinder diesel engine, providing high torque output suitable for heavy-duty applications. Its large 120-gallon fuel tank enhances operational efficiency by reducing refueling frequency, making it ideal for extended field work. However, the weight and size could present challenges in maneuverability on smaller farms or uneven terrain.
| Description | Sisu 7.4L 6-cyl diesel |
| Fuel tank | 120gal / 454.2L |
TRANSMISSION
The Challenger MT645's power shift transmission offers smooth gear transitions and a total of 18 forward and 6 reverse gears, allowing for efficient speed adjustments for varied field conditions. The electro-hydraulic wet disc clutch enhances durability and performance under heavy load, but may require more maintenance due to its complexity. This tractor is ideal for diverse agricultural tasks where responsiveness and reliability are critical.
| Type | power shift |
| Gears | 18 forward and 6 reverse |
| Clutch | electro-hydraulic wet disc |
MECHANICAL
The Challenger MT645’s 4x4 MFWD system enhances traction and stability on varied terrain, making it ideal for heavy-duty fieldwork. Its 18-speed power shift transmission allows for seamless speed adjustments, which can optimize fuel efficiency and improve productivity during operations. However, the hydraulic wet disc brakes, while effective, may require regular maintenance to ensure consistent performance under heavy loads.
| Chassis | 4x4 MFWD 4WD |
| Steering | power |
| Brakes | hydraulic wet disc |
| Cab | Cab standard with air-conditioning. |
| Transmission | 18-speed power shift |
HYDRAULICS
| Type | closed center pressure flow compensated (PFC) |
| Pressure | 2900psi / 200.0bar |
| Valves | 4 |
| Total flow | 29gpm / 109.8lpm/39gpm / 147.6lpm |
TRACTOR HITCH
| Rear Type | III |
| Rear lift (at 24 | 18400lbs / 8346kg |
POWER TAKE-OFF (PTO)
| Rear PTO | independent |
| Rear RPM | 1000 |
| Engine RPM | 1000@2091 |
CHALLENGER MT645 TIRES
The Challenger MT645 features an Ag front tire size of 14.9R30 and a rear tire size of 18.4R42, which provides a balanced weight distribution and enhanced traction on uneven terrain. This configuration is advantageous for heavy tillage and row crop applications due to improved flotation and reduced soil compaction. However, the larger rear tires may limit maneuverability in tight spaces, challenging operations in smaller fields or orchards.
| Ag front | 14.9R30 |
| Ag rear | 18.4R42 |
DIMENSIONS
| Wheelbase | 121inches / 307cm |
| Length | 203inches / 515cm |
| Width | 98.2inches / 249cm *Minimum width |
| Height (cab) | 121inches / 307cm |
| Shiping weight | 19000lbs / 8618kg |
DIMENSIONS & TIRES
The Challenger MT645, with a 121-inch wheelbase and a weight of 19,000 lbs, provides a solid stability for both field and transport operations, enhancing its ability to manage heavy loads. The front tire size of 14.9R30 and the rear tire size of 18.4R42 optimize traction and flotation in various soil conditions, making it suitable for tillage and harvesting tasks. However, the weight also presents challenges in compacted soils, which can affect soil health and crop yields if not managed with proper machinery practices.
| Wheelbase | 121inches / 307cm |
| Weight | 19000lbs / 8618kg |
| Front tire | 14.9R30 |
| Rear tire | 18.4R42 |
ELECTRICAL
| Ground | negative |
| Charging system | alternator |
| Battery volts | 12 |