International Harvester

666 Hydro (Gas) (1976-1972)

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Tractor Info


Standard and high-clearance versions of the Farmall 666 tractors were built during a 1972-76 run. Nearly 70 PTO horsepower was available in the 666 diesel and gasoline models. In the Nebraska tests, Farmall 666 tractors demonstrated a drawbar pull of approximately 8,000 pounds. With the increasing size of farm units, the 666 became an intermediate model, whereas just a few years earlier, it could have easily topped the line. This unit featured a pro­tective frame and canopy. Hydrostatic drive, dual rear wheels, and a fully enclosed cab were optional features found on this Farmall 966 Specially designed rubber mountings absorbed vibration, reducing noise within the cab and contributing to greater operator comfort with less fatigue. Specially honed wet cylinder sleeves minimized overhaul costs and spin-oi type oil and air filters simplified maintenance.

Tractor Info

Engine: IH

Cylinders: 6

Bore & Stroke:


CID: 291

Fuel: Gasoline

Main Fuel Tank Cap:

Aux Fuel Tank Cap:


Cooling Capacity:

Drawbar HP: 58.01

PTO HP: 69.61

Weight: 7250 lbs

Length: inches

Width: inches

Height: inches

Number of Gears: Hydro


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Last Updated: September 12th, 2022

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