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Years in Production / 1972–1976
International Harvester
666
Explore the specifications, hardware, and original references for the International Harvester 666.
75hp
Source index power
2WD Only
Drive
1972–1976
Production years
International Harvester
Manufacturer
666 / 01
At a glance
Overview
1972 - 1976
Row-Crop tractor
Production
Row-Crop tractor
Built in Rock Island, Illinois, USA
Torque amplifier was an option. In 1973, the hydrostatic version of the 666 was renamed the 70 Hydro.
- Manufacturer
- International Harvester
- Total Built
- 9,367
- Original Price
- $11,875
Mechanical
Two-wheel drive
Power steering
Dry disc brakes
Open operator station. Two-post ROPS or canopy optional. Cab available with air-conditioning.
Hydraulics
- Type
- open center
- Pump Flow
- 12 gpm45.4 lpm
Hitch
- Rear Type
- II
- Type
- IH Fast Hitch
Pto
- Rear Pto
- independent
- Rear Type
- 540 (1.375)
Electrical
- Charging System
- alternator
- Battery Volts
- 12
666 / 02
Under the hood
Engine Detail (Option 1)
International Harvester D312
diesel
6-cylinder
liquid-cooled
- Displacement
- 312 ci5.1 L
- Bore Stroke
- 3.875x4.410 inches98 x 112 mm
- Power Gross
- 75 hp55.9 kW
- Fuel System
- direct injection
- Air Cleaner
- dual stage dry
- Compression Ratio
- 17:1
- Rated Rpm
- 2000
- Starter Volts
- 12
- Coolant Capacity
- 21 qts19.9 L
- Fuel Type
- diesel
- Cylinders
- 6
- Cooling
- liquid-cooled
Engine Detail (Option 2)
International Harvester C291
gasoline
6-cylinder
liquid-cooled
- Displacement
- 291 ci4.8 L
- Bore Stroke
- 3.75x4.39 inches95 x 112 mm
- Power Gross
- 75 hp55.9 kW
- Air Cleaner
- dual stage dry
- Compression Ratio
- 7.5:1
- Rated Rpm
- 2000
- Starter Volts
- 12
- Coolant Capacity
- 21 qts19.9 L
- Fuel Type
- gasoline
- Cylinders
- 6
- Cooling
- liquid-cooled
Engine Options
International Harvester 5.1L 6-cyl diesel
International Harvester 4.8L 6-cyl gasoline
- Gas Fuel Tank
- 33 gal124.9 L
- Diesel Fuel Tank
- 31 gal117.3 L
Engine Options
International Harvester 5.1L 6-cyl diesel
International Harvester 4.8L 6-cyl gasoline
666 / 03
Gears & controls
Transmission (Option 1)
- Transmission
- sliding gear
- Gears
- 5 forward and 1 reverse
Transmission (Option 2)
- Transmission Type
- hydrostatic
- Gears
- infinite forward and reverse
Transmission (Option 3)
- Transmission
- Torque-Amplifier
- Transmission Type
- two-speed power shift
- Gears
- 10 forward and 2 reverse
- Clutch
- dry disc
Transmission Options
5-speed
hydrostatic
10-speed two-speed power shift
666 / 04
Size. Stance. Footprint.
Dimensions
- Length
- 161 in408 cm
- Width
- 87 in220 cm
- Height
- 77 in195 cm
- Wheelbase
- 103 in261 cm
- Front tread
- 50 in127 cm
- Rear tread
- 50 in127 cm
Dimensions And Tires
- Wheelbase
- 103 inches261 cm
- Weight
- 6780 to 7420 pounds
- Front Tire
- 7.50-16
- Rear Tire
- 15.5-38
Tires And Tracks
- Front Ag
- 7.50-16
- Rear Ag
- 15.5-38
See it in action
Videos
Watch International Harvester 666 videos from their original YouTube creators.
666 / 06
Tests (NTTL)
Tractor Tests
NTTL 1151: 312 diesel Torque Amplifier 2WD
NTTL 1152: gasoline Torque Amplifier 2WD
NTTL 1154: gasoline hydrostatic 2WD
NTTL 1155: diesel hydrostatic 2WD
Nebraska Tractor Test 1151
312 diesel Torque Amplifier 2WDNovember 3 - 14, 1973
PTO performance
Drawbar performance
Gear 3-Direct used for power test.
Gear 2-TA used for pull test.
- Id
- 1151
- Power At Rated Engine Speed
- 66.29 hp49.4 kW
- Fuel Use
- 4.7 gal/hour17.8 l/hour
- Fuel Use
- 4.6 gal/hour17.4 l/hour
- Max Power
- 58.01 hp43.3 kW
- Max Pull
- 8,012 lbs3634 kg
Nebraska Tractor Test 1152
Gasoline Torque Amplifier 2WDNovember 5 - December 3, 1973
PTO performance
Drawbar performance
Gear 3-Direct used for power test.
Gear 2-TA used for pull test.
- Id
- 1152
- Power At Rated Engine Speed
- 66.30 hp49.4 kW
- Fuel Use
- 12.0 gal/hour45.4 l/hour
- Fuel Use
- 5.7 gal/hour21.6 l/hour
- Max Power
- 57.29 hp42.7 kW
- Max Pull
- 7,981 lbs3620 kg
Nebraska Tractor Test 1154
Gasoline hydrostatic 2WDNovember 14 - December 3, 1973
PTO performance
Drawbar performance
- Id
- 1154
- Power At Rated Engine Speed
- 69.61 hp51.9 kW
- Fuel Use
- 6.9 gal/hour26.1 l/hour
- Fuel Use
- 5.8 gal/hour22.0 l/hour
- Fuel Use
- 7.7 gal/hour29.1 l/hour
- Power At Rated Pto Speed
- 64.10 hp47.8 kW
- Max Power
- 53.86 hp40.2 kW
- Max Pull
- 8,427 lbs3822 kg
Nebraska Tractor Test 1155
Diesel hydrostatic 2WDNovember 14 - December 3, 1973
PTO performance
Drawbar performance
- Id
- 1155
- Power At Rated Engine Speed
- 69.51 hp51.8 kW
- Fuel Use
- 5.6 gal/hour21.2 l/hour
- Fuel Use
- 5.3 gal/hour20.1 l/hour
- Power At Rated Pto Speed
- 65.41 hp48.8 kW
- Max Power
- 53.10 hp39.6 kW
- Max Pull
- 8,310 lbs3769 kg