Compare/Allis Chalmers 7580 vs Allis Chalmers HD21

Allis Chalmers 7580 vs Allis Chalmers HD21

Verdict: Allis Chalmers 7580 vs Allis Chalmers HD21

The Allis Chalmers 7580 and the Allis Chalmers HD21 are both tractors — here is how they stack up on the figures that matter. Allis Chalmers HD21 leads on rated power with 225 hp against 186 hp. Allis Chalmers HD21 is the lighter machine (20,638 kg vs 23,100 kg), which helps on soft ground and transport, while the heavier model carries more ballast for traction-limited draft work. Allis Chalmers 7580 holds more fuel (643.5 L vs 511.0 L) for longer stints between fills. Allis Chalmers 7580 is the newer design (1976 vs 1954). In short: choose the Allis Chalmers HD21 for outright pulling power, or the Allis Chalmers 7580 if a tighter budget and lighter footprint matter more. Compare the full spec tables below before booking a demo.

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Acreage600 acBudgetMain crop / use

Fit & specs

Allis Chalmers

Fit score

Best match

Clear

Allis Chalmers

Fit score

Best match

Clear

Rated power

186 hp

225 hp

Confidence

40%

Guide price

—

Overview

Manufacturer

Allis ChalmersReference

With 20.8x38 rear tires.Reference

Drawbar performanceReference

Total built

1610Reference

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Original price

$63,084Reference

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Steering

hydrostatic powerReference

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Drive

—

crawlerReference

Engine

Fuel tank

643.5 LReference

511.0 LReference

Drawbar (claimed)

114.1 kWReference

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Drawbar (tested)

114.6 kWReference

100.8 kWReference

Displacement

7.0 LReference

13.8 LReference

Bore/Stroke

108 x 127 mmReference

133 x 165 mmReference

Air cleaner

dryReference

oil bathReference

Compression

16:1Reference

13.3:1Reference

Rated RPM

2550Reference

1800Reference

Idle RPM

775-2750Reference

—

Firing order

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

—

Starter volts

12Reference

24Reference

Oil capacity

23.7 LReference

—

Coolant capacity

36.0 LReference

75.7 LReference

Power at rated engine speed

139.0 kWReference

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Max power

114.6 kWReference

100.8 kWReference

Engine

—

167.8 kWReference

Power

—

167.8 kWReference

Transmission

Power DirectorReference

—

Gears

20 forward and 4 reverseReference

2 forward and 1 reverseReference

PTO & Hydraulics

PTO (claimed)

138.7 kWReference

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PTO (tested)

139.0 kWReference

—

Type

partial power shiftReference

torque converterReference

Valves

3 to 4Reference

—

Pump flow

87.1 lpmReference

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Total flow

283.5 lpmReference

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Rear Type

IIIReference

—

Rear PTO

independentReference

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Rear PTO Type

1000Reference

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Dimensions

Wheelbase

320 cmReference

—

Weight

23100 to 23510 poundsReference

20638 kgReference

Front tire

20.8x38Reference

—

Rear tire

20.8x38Reference

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Ag front

18.4x38Reference

—

Ag rear

18.4x38Reference

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Length

571 cmReference

502 cmReference

Width

303 cmReference

—

Height (hood)

216 cmReference

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Height (exhaust)

381 cmReference

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Ground clearance

43 cmReference

—

Front tread

157 to 312 cmReference

—

Rear tread

157 to 312 cmReference

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Shipping

10478 kgReference

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Operating

10664 kgReference

—

Ballasted

11340 kgReference

—

Height

—

251 cmReference

7580 Serial Numbers

1976

1001Reference

—

1977

1288Reference

—

1978

1605Reference

—

1979

2218Reference

—

1980

2486Reference

—

1981

2717Reference

—

Location:

Front frame, rear left sideReference

Steering clutch housing or instrument panelReference

Final

3018Reference

—

Electrical

Charging system

alternatorReference

—

Batteries

4Reference

—

Battery volts

12Reference

—

Test results

Fuel use

47.7 l/hourReference

—

Max pull

10573 kgReference

18399 kgReference

Speeds

HD21 Serial Numbers

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.