Production years
1975-1977
Allis-Chalmers tractor ยท 1975-1977
Allis-Chalmers 7040 Tractor
The Allis-Chalmers 7040 is a 7000 Series row-crop tractor from the mid-1970s, built for serious tillage and PTO work. Its 7.0 L six-cylinder diesel produced about 136 tested PTO hp, while its Acousta cab and power-shift transmission options made it a well-regarded large Allis work tractor.
Engine
Allis-Chalmers 7.0 L, 426 cu. in. inline 6-cylinder diesel
Power
136.49 hp tested PTO; 114.34 hp tested drawbar
Weight
Approx. 11,700 lb operating
Allis-Chalmers 7040 specifications
| Production years | 1975-1977 |
|---|---|
| Engine | Allis-Chalmers 7.0 L, 426 cu. in. inline 6-cylinder diesel |
| Power | 136.49 hp tested PTO; 114.34 hp tested drawbar |
| Transmission | 12-speed or 20-speed partial power shift |
| Weight | Approx. 11,700 lb operating |
| Fuel type | Diesel |
| PTO | Independent 540/1,000 rpm rear PTO |
| Hydraulics | Closed-center system; 22 gpm pump flow |
What the 7040 is used for
The 7040 was aimed at high-acreage row-crop operations needing a tractor for heavy tillage, large planters, forage harvesting, and PTO-driven equipment. Its enclosed cab made it better suited to long workdays than many earlier tractors.
Owners still use these tractors for field work, hay and forage operations, grain-auger duty, and pulling events. Its weight and power also make it a capable tractor for large mounted or drawn implements when properly maintained.
Why the Allis-Chalmers 7040 stands out
The 7040 is popular for its strong 426 diesel, good PTO performance, and the comfort advantage of the Acousta cab. It represents an important period in Allis-Chalmers' move toward larger, more operator-friendly tractors, and it retains an active collector and parts network.
Buying a used Allis-Chalmers 7040
Operate every transmission range and power-shift step when the oil is warm, checking for hesitation, slipping, or abnormal noise. Inspect hydraulic performance, wet brakes, differential lock, engine cooling, turbocharger condition, and cab air-conditioning components; repair history matters greatly on cab, transmission, and hydraulic work. Confirm specifications by serial number with TractorData.com or factory records.
Allis-Chalmers 7040 frequently asked questions
How much PTO horsepower does an Allis-Chalmers 7040 have?
The commonly cited tested PTO figure is about 136.5 hp.
What engine is in a 7040?
It uses an Allis-Chalmers 426-cubic-inch, 7.0 L inline six-cylinder diesel.
Is the 7040 a good tractor for modern farm use?
Yes, it can remain useful for heavy PTO and drawbar work, provided the transmission, hydraulics, cooling system, and cab systems are in sound condition.
Specifications are commonly cited figures for general reference; exact figures vary by year and serial number, so confirm against TractorData.com and the machine's records. Values and prices of used tractors vary by condition and region. Page updated Aug 4, 2026.