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Years in Production / 1979–1981
Big Bud
400/20
Explore the specifications, hardware, and original references for the Big Bud 400/20.
No photo
400hp
Source index power
4x4 Only
Drive
1979–1981
Production years
Big Bud
Manufacturer
400/20 / 01
At a glance
Production
Four-wheel Drive (4WD) tractor
Built in Havre, Montana, USA
Original price was $109,000 in 1978
- Manufacturer
- Big Bud
Mechanical
Four-wheel drive
Articulated power steering
Pneumatic drum brakes
Cruiser Cab standard with air-conditioning.
- Final Drives
- planetary
Hydraulics
- Type
- closed center load sensing
- Valves
- 4
- Pump Flow
- 36 gpm136.3 lpm
- Steering Flow
- 35 gpm132.5 lpm
Electrical
- Ground
- negative
- Charging System
- alternator
- Charging Amps
- 75
- Battery Volts
- 12
400/20 / 02
Under the hood
Engine Detail
Detroit Diesel 8V-92T
turbocharged diesel
8-cylinder
liquid-cooled
- Displacement
- 736 ci12.1 L
- Bore Stroke
- 4.84x5.00 inches123 x 127 mm
- Power
- 400 hp298.3 kW
- Compression Ratio
- 19:1
- Rated Rpm
- 2100
- Starter
- electric
- Starter Volts
- 24
- Cylinders
- 8
- Cooling
- liquid-cooled
Engine Options
Detroit Diesel 12.1L 8-cyl diesel
- Fuel Tank
- 550 gal2081.8 L
400/20 / 03
Gears & controls
Transmission
- Transmission
- Fuller Roadranger RT 12513
- Transmission Type
- gear
- Gears
- 12 forward and 2 reverse
400/20 / 04
Size. Stance. Footprint.
Dimensions And Tires
- Wheelbase
- 150 inches381 cm
- Weight
- 40000 lbs18144 kg
- Front Tire
- 24.5-32
- Rear Tire
- 24.5-32
Tires And Tracks
- Front Ag
- 24.5-32
- Front Ag
- 30.5-32
- Rear Ag
- 24.5-32
- Rear Ag
- 30.5-32