Head to head · Agricultural

Allis Chalmers HD21 vs Caterpillar D8L SA Special Application

Allis Chalmers HD21 Tractor
Allis ChalmersModel A

Allis Chalmers HD21

Agricultural

power
225 hp
displacement
844 ci
Cylinders
6
Forward gears
2
Full HD21 specs
Allis ChalmersAllis Chalmers HD21
vs
CaterpillarCaterpillar D8L SA Special Application

How they compare

Headline specs vs. the whole Agricultural

n = 829–1,130

Engine Power

▲ D8L SA Special Application higher · +175 hp (+78%)
HD21225 hp
D8L SA Special Application400 hp
Median Agricultural Tractor110 hp

HD21 is in the 84th percentile; D8L SA Special Application is in the 97th · 1,028 models

Engine Displacement

▲ D8L SA Special Application higher · +255 ci (+30%)
HD21844 ci
D8L SA Special Application1,099 ci
Median Agricultural Tractor336 ci

HD21 is in the 96th percentile; D8L SA Special Application is in the 99th · 1,083 models

Cylinders

▲ D8L SA Special Application higher · +2 (+33%)
HD216
D8L SA Special Application8
Median Agricultural Tractor5.5

HD21 is in the 74th percentile; D8L SA Special Application is in the 99th · 1,130 models

Forward Gears

▲ D8L SA Special Application higher · +1 (+50%)
HD212
D8L SA Special Application3
Median Agricultural Tractor16

HD21 is in the 1st percentile; D8L SA Special Application is in the 1st · 972 models

HD21 (A)D8L SA Special Application (B)Median Agricultural Tractor

Full comparison

Every spec, side by side

General Information

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
ManufacturerAllis ChalmersCaterpillar—
ModelHD21D8L SA Special Application—
CategoryAgriculturalCrawler, Agricultural—

Engine

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
ManufacturerAllis-ChalmersCaterpillar—
ModelNot recorded3408—
Power Output225hp400hp▲ D8L SA Special Application+175 hp · +78%
Rated RPM1,800RPM1,900RPM▲ D8L SA Special Application+100 RPM · +6%
Cylinders68▲ D8L SA Special Application+2 · +33%
Displacement844ci1,099ci▲ D8L SA Special Application+255 ci · +30%
Bore5.3in5.4in▲ D8L SA Special Application+0.1 in · +2%
Stroke6.5in6in▲ HD21+0.5 in · +8%

Transmission

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
TypeTorque ConverterPower Shift—

Dimensions & Weight

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
Length198in215in▲ D8L SA Special Application+17 in · +9%
WidthNot recorded136in—
Height99inNot recorded—
Operating Weight45,500lb80,820lb▲ D8L SA Special Application+35,320 lb · +78%

Hydraulics

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
System TypeNot recordedLoad sensing—

Chassis & Drive

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
Chassis TypeNot recordedCrawler—
Brake TypeNot recordedWet disc—

Electrical

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
Starter TypeElectricElectricSame

Capacities

SpecAllis Chalmers HD21Caterpillar D8L SA Special ApplicationDifference
Coolant20gal24.5gal▲ D8L SA Special Application+4.5 gal · +23%

Category context

Both models against the field

Engine Power

median 110 hp
A · 84th percentile (225 hp)B · 97th percentile (400 hp)

Engine Displacement

median 336 ci
A · 96th percentile (844 ci)B · 99th percentile (1,099 ci)

Cylinders

median 5.5
A · 74th percentile (6)B · 99th percentile (8)

Forward Gears

median 16
A · 1st percentile (2)B · 1st percentile (3)

Operating Weight

median 10,914 lb
A · 99th percentile (45,500 lb)B · 99th percentile (80,820 lb)
A · HD21B · D8L SA Special ApplicationMedian Agricultural Tractor
Full spec pageAllis Chalmers HD21Full spec pageCaterpillar D8L SA Special Application