International Harvester 966

The International Harvester 966 is a tractor produced by International Harvester. It is equipped with a 414 ci 6.8 L engine. The listed engine power is Diesel (listed): 91 hp / 67.9 kW. Transmission: Torque Amplifier. Operating weight: 11116 to 11700 pounds.

Engine Power

Diesel (listed): 91 hp / 67.9 kW

Fuel & Capacities

37 gal 140.0 L

Transmission

Torque Amplifier

Operating Weight

11116 to 11700 pounds

Overview

	1971 - 1976 66 SeriesRow-Crop tractor 66 Series Row-Crop tractor

Production
Manufacturer	International Harvester
Row-Crop tractor
Built in Rock Island, Illinois, USA
Total built	21,017
Original price was $18,000 in 1976

Variants
Hi-Clear	high-crop model

International Harvester 966 Engine
International Harvester 6.8L 6-cyl diesel
Engine details ...

International Harvester 966 Power
Engine	91 hp 67.9 kW
Drawbar (claimed)	84 hp 62.6 kW
PTO (claimed)	95 hp 70.8 kW
Drawbar (tested)	85.21 hp 63.5 kW
PTO (tested)	100.80 hp 75.2 kW
Performance test details ...

Mechanical
Two- or four-wheel drive
Power steering
Independent hydraulic dry disc brakes
Cab optional with heat and air-conditioning.

Capacity
Fuel	37 gal 140.0 L
Hydraulic system	22.5 gal 85.2 L

Hydraulics
Type	open center
Capacity	22.5 gal 85.2 L
Pressure	2000 psi 137.9 bar
Valves	1 to 4
Pump flow	12 gpm 45.4 lpm
Total flow	21 gpm 79.5 lpm
Steering flow	9 gpm 34.1 lpm
Steering press.	1550 psi 106.9 bar

Tractor hitch
Rear Type	II
Rear lift (at 24"/610mm)	4400 lbs 1995 kg
Type	IH Fast Hitch
Rear lift	5000 lbs (at 24 inches) 2268 kg

Power Take-off (PTO)
Rear PTO	independent
Rear PTO Type	540/1000

Dimensions & Tires
Wheelbase	105 inches 266 cm
Weight	11116 to 11700 pounds
Front tire	9.5L-15
Rear tire	18.4-34
Full dimensions and tires ...

Electrical
Charging amps	32
Batteries	2
Battery volts	6
Battery AH	172

References

766, 966, 1066 and 1466 Tractors published in 1972, by International Harvester
766, 966, 1066 and 1466 Tractors published in 1973, by International Harvester
27PS-115PS published in 1975, by International Harvester

Engine

Engine Detail — 414 ci / 6.8 L Diesel

Manufacturer	International Harvester D414
Fuel Type	Diesel
Configuration	6-cylinder, liquid-cooled
Displacement	414 ci 6.8 L
Bore/Stroke	4.30x4.75 inches 109 x 121 mm
Power	91 hp 67.9 kW
Air cleaner	dual dry elements
Rated RPM	2400 (early)
	2600 (late)
Firing order	1-5-3-6-2-4
Oil capacity	12 qts 11.4 L
Coolant capacity	24 qts 22.7 L

Transmission

Transmission options
8-speed gear
16-speed two-speed power shift
hydrostatic

Transmission — 8 forward and 4 reverse gear

Type	gear
Gears	8 forward and 4 reverse
Clutch	dry disc
Oil capacity	90 qts 85.2 L
Four gears each provided in high, low, and reverse ranges.
With 18.4-34 rear tires.

Transmission — Torque Amplifier

Transmission	Torque Amplifier
Type	two-speed power shift
Gears	16 forward and 8 reverse
Clutch	dry disc
The Torque Amplifier (TA) provides a shift-on-the-move underdrive to the standard transmission. In any gear and range, the transmission can be shifted from direct drive (DD) to the slower TA speed by simply pulling the TA lever back. No clutching or stopping is needed.
With 18.4-34 rear tires.

Transmission — infinite forward and reverse hydrostatic

Type	hydrostatic
Gears	infinite forward and reverse
The hydrostatic transmission option ended in 1973 when the Hydro 100 began production.

Dimensions

International Harvester 966 Tires
Ag front	9.5L-15
Ag rear	18.4-34

Dimensions
Wheelbase	105 inches 266 cm
Length	165 inches 419 cm
Width	98 inches 248 cm
Height (exhaust)	105 inches 266 cm
Ground clearance	14 inches 35 cm

International Harvester 966 Weight
Operating	11,116 lbs (gear) 5042 kg
	11,700 lbs (hydro) 5307 kg
Ballasted	13,500 lbs 6123 kg

Tests

Tractor Tests
NTTL 1082: 2400rpm diesel gear/TA 2WD
NTTL 1095: diesel hydrostatic 2WD
NTTL 1123: 2600rpm diesel gear/TA 2WD

Nebraska Tractor Test 1082
2400rpm diesel gear/TA 2WD October 5 - 19, 1971 Link: Nebraska Tractor Test 1082 file
PTO performance
Power at rated engine speed	96.04 hp 71.6 kW
Fuel use	6.5 gal/hour 24.6 l/hour
Power at rated PTO speed	93.5 hp 69.7 kW
Fuel use	5.9 gal/hour 22.3 l/hour
Drawbar performance
Max power	80.4 hp 60.0 kW
Fuel use	6.4 gal/hour 24.2 l/hour
Gear 1-Hi-TA used for power test.
Max pull	10,041 lbs 4554 kg
Gear 3-Lo-TA used for pull test.

Nebraska Tractor Test 1095
Diesel hydrostatic 2WD April 28 - May 12, 1972 Link: Nebraska Tractor Test 1095 file
PTO performance
Power at rated engine speed	91.38 hp 68.1 kW
Fuel use	7.2 gal/hour 27.3 l/hour
Power at rated PTO speed	88.29 hp 65.8 kW
Fuel use	6.4 gal/hour 24.2 l/hour
Drawbar performance
Max power	68.08 hp 50.8 kW
Fuel use	7.1 gal/hour 26.9 l/hour
Gear 5.4 MPH used for power test.
Max pull	8,909 lbs 4041 kg
Gear 2.77 MPH used for pull test.

Nebraska Tractor Test 1123
2600rpm diesel gear/TA 2WD April 20 - May 17, 1973 Link: Nebraska Tractor Test 1123 file
PTO performance
Power at rated engine speed	100.80 hp 75.2 kW
Fuel use	6.9 gal/hour 26.1 l/hour
Power at rated PTO speed	101.52 hp 75.7 kW
Fuel use	6.5 gal/hour 24.6 l/hour
Drawbar performance
Max power	85.21 hp 63.5 kW
Fuel use	6.9 gal/hour 26.1 l/hour
Gear 1-Hi-TA used for power test.
Max pull	10,036 lbs 4552 kg
Gear 3-Lo-TA used for pull test.

Photos

International Harvester 966 tractor photo

Recommended Implements & Sizing Guide

Engineering recommendations for International Harvester 966 based on its 91 HP power envelope and ASAE agricultural standards.

Implement & Operation	Recommended Size	Workload Rating	Engineering Notes
Moldboard PlowPrimary Tillage	4 to 5 Bottom (16-18")4 - 5 铧 (40-45 cm)	Heavy Duty	Heavy primary tillage; semi-mounted hitch recommended.
Rotary Cutter / MowerMowing & Clearing	7 to 8 ft (84-96 in)2.1 - 2.4 m	Heavy Duty	Heavy-duty twin spindle cutter for overgrown acreage.
Rotary TillerSeedbed Prep	78 to 84 in200 - 215 cm	Heavy Duty	Heavy commercial tiller with multi-speed gearbox.
Disc HarrowSecondary Tillage	10 to 14 ft Tandem / Offset3.0 - 4.2 m 重型交错耙	Heavy Duty	Aggressive residue cutting in corn/cotton stubble.
Hay BalerHay & Forage	4x4 to 4x5 Round Baler1.2x1.5 m 紧凑圆捆机	Heavy Duty	Silage and dry hay; 540 RPM PTO with slip-clutch.

Sizing & Soil Condition NoteActual implement sizing varies depending on local soil conditions (heavy clay vs sandy loam), field slope, and operating speed. Heavy tillage implements may require front ballast weights and wheel weights.

Fluids, Capacities & Working Autonomy

Standard fluid requirements, service intervals, and continuous runtime estimates for International Harvester 966.

Estimated Continuous Field Runtime: 7.8 hrs

Approximately 7.8 hours of continuous field operation at ~75% rated power on a full tank (37 gal / 140.1 L).

Estimated 75% Load Fuel Burn~4.7 gal/hr (17.9 L/hr)

Engine Crankcase Oil

SAE 15W-40 (Heavy Duty Diesel)

Standard Spec: API CK-4 / CJ-4 Heavy Duty

Service Interval: 150 – 250 Hours

Transmission & Hydraulic System

UTTO (Universal Tractor Transmission Oil)

Standard Spec: ISO VG 46 / 68 (Wet Brake & Trans Compatible)

Service Interval: 600 – 1000 Hours

Engine Cooling System

50/50 Ethylene Glycol Pre-mix

Standard Spec: ASTM D6210 / Heavy-Duty OAT Antifreeze

Service Interval: 2 Years / 1500 Hours