Compare/Farmall 656 vs Farmall 666

Farmall 656 vs Farmall 666

Verdict: Farmall 656 vs Farmall 666

The Farmall 656 and the Farmall 666 are both tractors — here is how they stack up on the figures that matter. Farmall 666 leads on rated power with 75 hp against 64 hp. Farmall 656 is the lighter machine (6,250 kg vs 6,780 kg), which helps on soft ground and transport, while the heavier model carries more ballast for traction-limited draft work. Farmall 666 is the newer design (1972 vs 1965). In short: choose the Farmall 666 for outright pulling power, or the Farmall 656 if a tighter budget and lighter footprint matter more. Compare the full spec tables below before booking a demo.

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Tell us about your operation

Acreage600 acBudgetMain crop / use

Fit & specs

Farmall

Fit score

Best match

Clear

Farmall

Fit score

Best match

Clear

Rated power

64 hp

75 hp

Confidence

40%

Guide price

—

Overview

Manufacturer

Farmall (a part of International Harvester)Reference

With 15.5-38 rear tires.Reference

Diesel hydrostatic 2WDNovember 14 - December 3, 1973Link: Nebraska Tractor Test 1155 fileReference

Total built

—

9,367Reference

Original price

—

$11,875Reference

Variants

2656

industrial tractorReference

—

IH 656

utility tractorReference

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Farmall 656

row-crop tractorReference

—

656HC

high-clearReference

—

Engine

Fuel tank

147.6 LReference

—

Plows

4-5Reference

—

Drawbar (tested)

39.7 kWReference

43.3 kWReference

Displacement

4.3 LReference

4.8 LReference

Bore/Stroke

90 x 112 mmReference

95 x 112 mmReference

Air cleaner

dryReference

dual stage dryReference

Compression

8.8:1Reference

7.5:1Reference

Rated RPM

2300 (late)Reference

2000Reference

Firing order

1-5-3-6-2-4Reference

—

Starter volts

12Reference

Oil capacity

64.4 LReference

—

Coolant capacity

19.9 LReference

Power at rated engine speed

49.1 kWReference

51.8 kWReference

Max power

37.4 kWReference

39.6 kWReference

Gas Fuel tank

—

124.9 LReference

Diesel Fuel tank

—

117.3 LReference

Engine (gross)

—

55.9 kWReference

Drawbar (claimed)

—

40.3 kWReference

Power (gross)

—

55.9 kWReference

Fuel system

—

direct injectionReference

Transmission

hydrostaticReference

Torque-AmplifierReference

Gears

infinite forward and reverse (2-range)Reference

10 forward and 2 reverseReference

Clutch

—

dry discReference

PTO & Hydraulics

Gasoline PTO (claimed)

47.6 kWReference

—

Diesel PTO (claimed)

45.9 kWReference

—

PTO (tested)

49.3 kWReference

51.9 kWReference

Type

two-speed power shiftReference

Rear valves

1 or 2Reference

—

Total flow

45.4 lpmReference

—

Rear Type

IIReference

Control

position and draft controlReference

—

Rear PTO

independentReference

Rear PTO Type

540/1000Reference

540 (1.375)Reference

Engine RPM

1000@1800Reference

—

Power at rated PTO speed

45.3 kWReference

48.8 kWReference

PTO (claimed)

—

51.5 kWReference

Pump flow

—

45.4 lpmReference

Dimensions

Wheelbase

244 cmReference

261 cmReference

Weight

6250 to 7230 poundsReference

6780 to 7420 poundsReference

Front tire

6.00-16Reference

7.50-16Reference

Rear tire

15.5-38Reference

Ag front

6.00-16Reference

7.50-16Reference

Ag rear

15.5-38Reference

Length

386 cmReference

408 cmReference

Width

220 cmReference

Height (steering wheel)

195 cmReference

Clearance (front axle)

53 cmReference

Clearance (drawbar)

33 cmReference

35 cmReference

Front tread

40 cmReference

142 to 203 cmReference

Rear tread

127 to 243 cmReference

Shipping

2957 kgReference

—

Operating

3279 kgReference

—

Ballasted

4188 kgReference

—

Shipping weight

—

3365 kgReference

Farmall 656 attachments

656 Serial Number Location

656 Serial Numbers

1965

8501Reference

—

1966

15505Reference

—

1967

24372Reference

—

1968

32007Reference

—

1969

38861Reference

—

1970

42518Reference

—

1971

45497Reference

—

1972

47951Reference

7500Reference

Electrical

Charging amps

55Reference

—

Batteries

2 (diesel)Reference

—

Battery volts

6 (diesel)Reference

12Reference

Battery AH

130 (diesel)Reference

—

Charging system

—

alternatorReference

Attachment overview

Test results

Fuel use

24.2 l/hourReference

20.1 l/hourReference

Max pull

3441 kgReference

3769 kgReference

Speeds

666 Serial Numbers

1973

—

8200Reference

1974

—

11585Reference

1975

—

13131Reference

1976

—

15739Reference

Location:

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Clutch housing, right sideReference

Fit score weighs budget, operation size, crop match and data confidence against the details above. It’s guidance, not advice — always confirm with a dealer demo.