Allis Chalmers

Allis Chalmers 8550

The Allis Chalmers 8550 is a four-wheel drive (4WD) tractor produced from 1978 to 1981. It features a powerful 12.0L 6-cylinder turbocharged diesel engine delivering 300 hp. The tractor has a 20-speed partial power shift transmission with Power Director and hydrostatic power steering. It includes hydraulic wet disc brakes and an Acousta Cab II with heat and air-conditioning. The 8550 has a closed center hydraulic system with 3 or 4 valves and a pump flow of 74.9 gpm. It is equipped with a rear independent PTO of 1000 rpm and a rear hitch type IV/III. Dimensions include a 126 inch wheelbase, 285 inch length, and widths up to 119.5 inches with long axle. The tractor weighs between 26,400 and 29,360 lbs depending on configuration. Tires vary with multiple options for front and rear. Electrical system features a negative ground, alternator charging, and four 12-volt batteries.

Power300 hp

Founded1978 - 1981

Model8550

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Technical Specifications

Detailed specifications and technical data for Allis Chalmers 8550

Power

Engine	300 hp (223.7 kW)
PTO (tested)	253.88 hp (189.3 kW)
PTO (claimed)	250 hp (186.4 kW)
Drawbar (tested)	217.92 hp (162.5 kW)
Drawbar (claimed)	210 hp (156.6 kW)

Tires

Ag rear	18.4x38, 20.8x34, 20.8x38, 23.1x30, 24.5x32, 30.5x32
Ag front	18.4x38, 20.8x34, 20.8x38, 23.1x30, 24.5x32, 30.5x32

Engine

Type	turbocharged diesel
Model	Allis Chalmers 6120T
Power	300 hp (223.7 kW)
Cooling	liquid-cooled inline
Idle RPM	775-2800
Cylinders	6-cylinder 24-valve
Fuel tank	170 gal (643.5 L)
Rated RPM	2500
Air cleaner	dry
Bore/Stroke	5.25x6.25 inches (133 x 159 mm)
Compression	16.25:1
Displacement	731 ci (12.0 L)
Firing order	1-5-3-6-2-4
Oil capacity	46 qts (2 filter) (43.5 L), 60 qts (3 filter) (56.8 L)
Starter volts	12
Coolant capacity	72 qts (68.1 L)
Intake valve clearance	0.015 inches (hot) (0.381 mm)
Exhaust valve clearance	0.020 inches (hot) (0.508 mm)

Height

Cab	139 inches (353 cm)
Hood	90.3 inches (229 cm)
Exhaust	154 inches (391 cm)

Weight

Shipping	26,400 lbs (duals) (11975 kg)
Ballasted	29,360 lbs (13317 kg)
Operating	27,040 lbs (12265 kg)

Dimensions

Width	95.5 inches (242 cm), 119.5 inches (long axle) (303 cm)
Length	285 inches (723 cm)
Wheelbase	126 inches (320 cm)
Rear tread	62 to 123 inches (157 to 312 cm)
Front tread	62 to 123 inches (157 to 312 cm)
Ground clearance	17 inches (43 cm)

Electrical

Ground	negative
Batteries	4
Battery volts	12
Charging system	alternator

Hydraulics

Type	closed center
Valves	3 or 4
Pump flow	74.9 gpm (283.5 lpm)

Mechanical

Cab	Acousta Cab II standard with heat and air-conditioning. Optional radio and 8 track tape deck.
Drive	Four-wheel drive
Brakes	Hydraulic wet discs brakes
Steering	hydrostatic power

Production