Comparing the Allis Chalmers HD21 and the Caterpillar D7G SA Special Application

This page provides a detailed comparison of the specifications for the Allis Chalmers HD21 and the Caterpillar D7G SA Special Application. Explore key differences and similarities across various aspects, including Power Output, Operating Weight and Cylinders.

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Allis Chalmers HD21 Tractor
Allis Chalmers HD21 Tractor
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SpecificationAllis Chalmers HD21Caterpillar D7G SA Special Application
General Information
Manufacturer
Allis Chalmers
Caterpillar
Model
HD21
D7G SA Special Application
Category
Agricultural
Crawler, Agricultural
Engine
Manufacturer
Allis-Chalmers
Caterpillar
Model
3306
Power Output
225hp
250hp
Rated RPM
1,800RPM
2,000RPM
Cylinders
6
6
Displacement
844ci
638ci
Bore
5.25in
4.75in
Stroke
6.5in
6in
Transmission
Type
Torque Converter
Gear
Dimensions & Weight
Length
198in
179in
Width
103in
Height
99in
Operating Weight
45,500lb
40,700lb
Hydraulics
System Type
Open Center
Chassis & Drive
Chassis Type
Crawler
Electrical
Starter Type
Electric
Electric
Capacities
Coolant
20gal
12gal