AgriculturalPerformance profile
Allis Chalmers HD21
The Allis Chalmers HD21 is a powerful tractor built for heavy-duty work. It has a strong diesel engine made by Allis-Chalmers with 6 cylinders. This engine can produce 225 horsepower, which is a lot of power for big jobs. The engine is cooled by liquid and has a supercharger to make it even stronger. This tractor is big and heavy, weighing 45,500 pounds. It's 198 inches long and 99 inches tall. The HD21 has a torque converter transmission with 2 forward gears and 1 reverse gear. This helps it move easily in different conditions. The tractor starts with an electric starter that uses 24 volts. It also has an oil bath air cleaner to keep the engine clean and running well. Allis Chalmers was known for making tough farm equipment. The HD21 shows this with its strong build and features. It can hold 80 quarts of coolant, which helps keep the engine cool during long work days. This tractor is made for farmers who need a reliable machine for big tasks on their farms.
ManufacturerAllis ChalmersPower225 hpEngine6-cylTransTorque Converter
Quick specs
- Category
- Agricultural
- Engine Power Output
- 225hp
- Operating Weight
- 45,500 lb
- Transmission
- Torque Converter
At a glance
How the HD21 compares
vs. Agricultural medianDistribution
Engine Power (hp)
Across all Agricultural tractors
225 hp · 84th
This model
13
Median 110 hp
282
This modelAgricultural tractorsMediann = 1,028
The HD21 ranks at the 84th percentile for engine power among recorded agricultural tractors.
Overview
About the Allis Chalmers HD21
The Allis Chalmers HD21 is a powerful tractor built for heavy-duty work. It has a strong diesel engine made by Allis-Chalmers with 6 cylinders. This engine can produce 225 horsepower, which is a lot of power for big jobs. The engine is cooled by liquid and has a supercharger to make it even stronger. This tractor is big and heavy, weighing 45,500 pounds. It's 198 inches long and 99 inches tall. The HD21 has a torque converter transmission with 2 forward gears and 1 reverse gear. This helps it move easily in different conditions. The tractor starts with an electric starter that uses 24 volts. It also has an oil bath air cleaner to keep the engine clean and running well. Allis Chalmers was known for making tough farm equipment. The HD21 shows this with its strong build and features. It can hold 80 quarts of coolant, which helps keep the engine cool during long work days. This tractor is made for farmers who need a reliable machine for big tasks on their farms.
Full specifications
Every recorded spec
General
| Manufacturer | Allis Chalmers |
|---|---|
| Model | HD21 |
| Category | Agricultural tractor |
| Operating weight | 45,500lb |
Engine
| Make | Allis-Chalmers |
|---|---|
| Power | 225hp |
| Cylinders | 6 |
| Displacement | 844ci |
| Bore | 5.25in |
| Stroke | 6.5in |
Transmission
| Type | Torque Converter |
|---|---|
| Forward gears | 2 |
| Reverse gears | 1 |
Dimensions
| Length | 198in |
|---|---|
| Height | 99in |
| Operating weight | 45,500lb |
Capacities
| Cooling system | 20gal |
|---|
Head to head
HD21 vs. Agricultural median
How the Allis Chalmers HD21 compares to other Agricultural tractors
| Spec | This model | Agricultural median | Difference | Percentile |
|---|---|---|---|---|
| Engine Power | 225 hp | 110 hp | +105% | 84th |
| Engine Displacement | 844 ci | 336 ci | +151% | 96th |
| Cylinders | 6 | 5.5 | +9% | 74th |
| Forward Gears | 2 | 16 | -87% | 1st |
| Operating Weight | 45,500 lb | 10,914 lb | +317% | 99th |
| Length | 198 in | 173 in | +15% | 77th |
| Height | 99 in | 111 in | -10% | 28th |
Medians and percentiles are computed from the agricultural tractors in our database with a recorded value for each spec (sample sizes 795–1,130 models).
Compare to tractors with similar specs
Commonly compared Allis Chalmers tractors
| Tractor | Engine Power | Operating Weight | Years | Compare |
|---|---|---|---|---|
| Allis Chalmers 7000 | 117 hp | 9,550 lb | 1975–1979 | Compare → |
| Allis Chalmers HD11 | 110 hp | 21,000 lb | 1955–1965 | Compare → |
| Allis Chalmers 160 | 40 hp | 4,674 lb | 1970–1975 | Compare → |
| Allis Chalmers 170 | — | 5,720 lb | 1968–1973 | Compare → |
| Allis Chalmers HD5 | — | 10,500 lb | 1946–1955 | Compare → |
Commonly compared tractors with similar horsepower from other brands
| Tractor | Engine Power | Operating Weight | Years | Compare |
|---|---|---|---|---|
| AGCO DT225 | 225 hp | 19,700 lb | 2002–2004 | Compare → |
| Belarus 7011 | 225 hp | 28,240 lb | — | Compare → |
| CaseIH 8950 | 225 hp | 18,340 lb | 1997–1998 | Compare → |
| CaseIH Magnum 225 | 225 hp | 19,000 lb | — | Compare → |
| CaseIH Magnum 215 | 221 hp | 21,035 lb | — | Compare → |
Explore
Allis Chalmers siblings
Explore
Similar-spec models
Gallery
Allis Chalmers HD21 photos
FAQ
Common questions
How powerful is the Allis Chalmers HD21?
The Allis Chalmers HD21 has an engine power output of 225 hp. It is powered by a 6-cylinder engine displacing 844 ci.
What type of transmission does the Allis Chalmers HD21 have?
The Allis Chalmers HD21 uses a Torque Converter transmission offering 2 forward gears.
What is the working weight of the Allis Chalmers HD21?
The operating weight of the Allis Chalmers HD21 is approximately 45,500 lb.
What routine service does the Allis Chalmers HD21 need?
Regular maintenance for the Allis Chalmers HD21 includes checking and changing engine oil, hydraulic fluid, and filters, plus routine inspections as recommended in the owner's manual. Always follow the manufacturer's maintenance schedule for specific intervals and procedures.