The Best International Harvester 1066 Reviews: Farming Expert for All Tasks!

International Harvester was one of the leading brands in the farming world in the 20th century. The International Harvester 1066 stood out for its power, efficiency, performance, and reliability. And our best International Harvester 1066 reviews will show you why.

If you want to learn its value and see why farmers appreciate the machine even today, read the specs, main features, and benefits below. It might become your number #1 choice.

Key Points:

  • The IH 1066 was one of the most popular machines due to its diesel engine, three transmission models (power shift, gear, and hydrostatic transmission), and variable speed models.
  • The machinery included outstanding coolant and oil capacity, total flow, and different gears to adjust the unit for multiple farming operations.
  • Finally, it’s price matched the quality, and farmers could select open or closed cab models.

International Harvester 1066 tractor: The best value for all farmers

If you’re wondering whether or not the International Harvester 1066 tractor should be your primary source, refer to the guidelines below and find all the critical factors the tractor offers.

International Harvester 1066 history

international harvester 1066 specs

The International Harvester 1066 tractor was a 2WD or 4WD row-crop tractor from the famous 66 Series. The International Harvester manufacturer produced the model in Rock Island, Illinois, between 1971 and 1976.

The tractor was specific for its three transmission types and diesel engine, 108 HP, and 2400 RPM. However, the company increased the power, and from 1973 the International Harvester 1066 tractor provided 2600 RPM.

For the six years of production, more than 50,000 models were produced, but then the show came to a halt (more info further in the review). The tractor was sold for the original price of $21,100 (1967.)

Over the years, the serial numbers have also changed so that farmers can find the following serial numbers:

  • 1971: 7101
  • 1972: 12677
  • 1973: 24205
  • 1974: 34949
  • 1975: 46855
  • 1976: 56672

International Harvester 1066 overall specs

The International Harvester 1066 was a good tractor for all farming tasks, thanks to its design and overall dimensions. The row-crop tractor was one of the most reliable models, as farmers could operate it efficiently, and it was ideal for smaller and larger farms.

Let’s see the specs.

Overall specs

Length 165 inches (419 cm)
Width 98 inches (248 cm)
Wheelbase 105 inches (266 cm)
Height (exhaust)11 inches (27 cm)
Clearance (drawbar)16 inches (40 cm)
Rear axle Bar: 3.25-inch diameter (82 mm)
Operating weight 12,148 lbs (5510 kg) (gear)
12,320 lbs (5588 kg) (hydro)
13,345 lbs (6053 kg) (duals)
Ballasted weight 15,260 lbs (6921 kg)
Fuel tank capacity 42 gal (159 L)

International Harvester 1066 engine 

The International Harvester 1066 model was specific for its diesel engine with six cylinders and a combustion chamber. International Harvester used the DT414 turbocharged 6-cylinder diesel engine, liquid-cooled. The engine was unique for its solid construction and effective rods and bolts, so it withstood the test of time. And the oil capacity/coolant capacity increased the engine quality, keeping it quiet and preventing overheating.

Diesel engine specs

Engine International Harvester DT414 turbocharged diesel 6-cylinder liquid-cooled, heavy block & crank
Fuel type Diesel 
Displacement 414 ci (6.8 l)
Bore/Stroke4.30×4.75 inches (109 x 121 mm)
Air cleaner Dual stage dry 
Rated RPM2400 (2600 after 1973)
Starter Electric 
Starter volts 12 V (2 x 6V batteries) 
Oil capacity 18 qts (17 l)
Coolant capacity 25 qts (23.7 l)

International Harvester 1066 mechanics

As a row-crop tractor, the International Harvester 1066 can be either 2WD or 4WD, with an open operator station, hydrostatic power steering, and three transmission types. You can choose the suitable transmission model based on the operations and speeds you need for optimal performance.

Mechanical specs

Chassis 2WD
4×4 MFWD 4WD 
Steering Power 
BrakesHydraulic dry disc brakes
Cab Open operator station. Two-post fixed ROPS is available. Cab available with optional air-conditioning.
Transmission model eight-speed gear
sixteen-speed partial power shift
Hydrostatic transmission

International Harvester 1066 transmission

The International Harvester 1066 model comes with three transmission types:

  1. gear type transmission with dry disc clutch (8 forward and four reverse gears), 
  2. partial power shift transmission with dry disc clutch (16 forward and eight reverse gears) 
  3. hydrostatic transmission with infinite (two-range) forward and reverse.

The tractor is versatile for multiple tasks, depending on its speed.

Transmission features

Transmission Transmission Torque amplifier 
Type Gear Type Partial power shift  
Gears eight forward, and four reverse Gears sixteen forward and eight reverse 
Clutch Dry discClutch Dry disc 

International Harvester 1066 power

1066 international problems

The International Harvester 1066 model was an excellent tractor, practical and robust for optimal performance. The IH Line tractor offered 108 HP and was an ideal model for full-scale farming. In addition, the IH tractor provided sufficient power for heavy-duty operations.

Power specs

Drawbar (claimed)108 HP (80.5 kW)
Drawbar (tested)105.95 HP (79 kW)
PTO (claimed)126 HP (94 kW)
PTO (tested)125.68 HP (93.7 kW)

International Harvester 1066 PTO and hitch

The International Harvester 1066 was a reliable row-crop tractor equipped with higher horsepower for its time. The tractor operated with 125 horsepower, and the PTO features improved its efficiency for multiple implements. The three-point hitch belongs to Category 2/Category 3, and you can attach various implements to complete the necessary farming operations.

PTO and hitch features

PTO specs Tractor hitch specs 
Rear PTO Independent Rear typelll/ll
Rear RPm 540/1000Rear lift (at 24 inches/610 mm)5600 lbs (2540 kg)

International Harvester 1066 hydraulic system

Thanks to hydraulics, the IH tractor could quickly transform the engine power into the implemented energy for maximum efficiency and strength. So, the farmers preferred it for less time-consuming work.

Hydraulics specs

Type Open center 
Pump flow 12 GPM (45.4 LPM)
Total flow 21 GPM (79.5 LPM)
Steering flow 9 GPM (34.1 LPM)

International Harvester 1066 tires

Due to the high-quality, durable tires, the tractor is ideal for all weather conditions and all farming tasks. There will be no delays, and the tires cannot damage so soon. Let’s see their features.

Tires specs

Ag front 11L-15
Ag rear 18.4-38

Why did the production stop?

The international Harvester 1066 was last made in 1976, and production stopped after more than 54,000 models. The tractor had multiple issues since it was good but far from perfect. Some main topics included:

  • Difficulties with battery installation – farmers struggled to put it in or out or change it due to specific positions.
  • Loudness level – the tractor was very loud, although the coolant and oil capacity operated well to prevent noise and keep the engine optimal. In addition, the open operator station only increased the noise level.
  • Limited performance compared to other tractors – the IH tractor was efficient for its time, especially in the 1970s, with increased horsepower. However, compared to its competitors (John Deere, Ford tractors, etc.), the tractor provided poor performance.

What are the alternatives?

The International Harvester 1066 compares with various John Deere models (4440, 4430, 4020). Let’s see their differences.

international harvester 1066 turbo

John Deere 4440 vs. International Harvester 1066

  • 1066 has half the price the 4440 offers 
  • The 4440 is more comfortable than the 1066
  • Both tractors offer more than 10 hours of work 
  • The JD is more popular than the IH tractor nowadays

John Deere 4020 vs. International Harvester 1066

  • The JD tractor had a smaller price than the IH 1066
  • The JD model is more agile and adaptable to all terrains than 1066
  • 1066 might not work with all of the attachments and similar tractor equipment

John Deere 4430 vs. International Harvester 1066

  • The 4430 has a more expensive price tag than the IH 
  • 1066 is not as versatile as the 4430, especially in winter conditions 
  • 1066 might have a better start; however, the performance cannot outmatch the 4430 
  • 1066 used more fuel than the 4430


As you can observe, the International Harvester 1066 was among the most popular tractors during the 1970s and could evade even the more advantageous models.

The farmers also chose the possibility of the cabbed model to reduce the noise the machinery might create. Hopefully, the review provides the answer to your questions.

Photo of author

Ben Bareja

Ben Bareja, the owner-founder-webmaster of This website was conceptualized primarily to serve as an e-library for reference purposes on the principles and practices in crop science, including basic botany. Read more here

Leave a Comment