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Tractor · 1954Unverified

Allis Chalmers HD21

Name: Allis Chalmers HD21
Brand: Allis Chalmers

Allis Chalmers HD21 — Model year 1954-19581958-1965 · 225 hp. Reference specifications; pending source verification.

The Allis Chalmers HD21 is a tractor with a rating of 225 horsepower, categorising it among the more powerful machines in its class. Manufactured from 1954 to 1965, this model features a 6-cylinder diesel liquid-cooled engine. The engine is coupled to a 2-speed gearbox, which drives a tracked undercarriage. The HD21 has a listed weight of 20638 kg and is suited to tasks covering approximately 600–1,500 acres.

Provisional listing — the headline figure is shown; full specifications are auto-generated and pending verification against published sources.

Rated power

225 hp

Max power

100.8 kW

Weight

20638 kg

Catalogue coverage

Variants represented

Richest spec table

34 rows

Recorded power

225 hp

Recorded weight

20638 kg

Transmissions

2-speed torque converter

Production years

1954-1965

Verified variants

No linked source document is currently displayed; verify critical figures with the manufacturer or dealer.

Hover a source tag to verify

Overview

ManufacturerAllis ChalmersReference

Agricultural Crawler tractorReference

Built in Springfield, Illinois, USAReference

DrivecrawlerReference

Contracting band brakesReference

Open operator station.Reference

Engine

Allis-Chalmers 13.8L 6-cyl dieselReference

Fuel tank511.0 LReference

Engine167.8 kWReference

Drawbar (tested)100.8 kWReference

Allis-ChalmersReference

supercharged dieselReference

6-cylinderReference

liquid-cooled vertical I-headReference

Displacement13.8 LReference

Bore/Stroke133 x 165 mmReference

Power167.8 kWReference

Air cleaneroil bathReference

Compression13.3:1Reference

Rated RPM1800Reference

Starter volts24Reference

Coolant capacity75.7 LReference

Max power100.8 kWReference

Transmission

2-speed torque converterReference

Typetorque converterReference

Gears2 forward and 1 reverseReference

Dimensions

Weight20638 kgReference

TracksReference

Length502 cmReference

Height251 cmReference

HD21 Serial Numbers

Location:Steering clutch housing or instrument panelReference

Test results

Diesel 2-speed crawlerJuly 6 - 18, 1955Link: Nebraska Tractor Test 550 fileReference

Drawbar performanceReference

Max pull18399 kgReference

Values normalized to UK metric units. Every figure is traced to at least one source; verified specs are cross-checked against two or more.

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