Allison 6610

In the realm of heavy-duty applications, the Allison S6610 and M6610 transmissions stand as paragons of engineering excellence. Designed for the rigorous demands of the oil field and heavy truck industries, these transmissions combine power, precision, and versatility to deliver unparalleled performance. This article delves into the detailed specifications, unique features, and diverse applications of the S6610 and M6610, highlighting why they are indispensable for demanding operations.


Horsepower and Input Speed:

The Allison S6610 and M6610 transmissions are built to accommodate significant horsepower and input speed ranges, making them versatile for a variety of demanding applications:

  • Horse Power Min: 2300 Hp
  • Horse Power Max: 3118 Hp
  • Input Speed Min: 850 rpm
  • Input Speed Max: 634 rpm

These specifications ensure that the transmissions can handle a wide array of engine outputs, maintaining optimal performance in various operational conditions.

Gearing and Oil Requirements:

With mechanical gearing, the S6610 and M6610 feature six forward gears and two reverse gears, providing the necessary control and adaptability for intricate operations. The recommended oil is C-4, 15W40, with a capacity of 18 gallons, ensuring efficient lubrication and long-term reliability.

Mounting and Weight:

Mounting options for these transmissions include direct SAE No.1 flywheel housing with flexplate drive and remote mounting options. The cradle mount uses engine flywheel housing mounting pads and transmission rear cover mounting pads, providing robust and flexible mounting solutions. The dry weight ranges from 2200 lb (998 kg) to additional weights for specific features, reflecting their lightweight yet durable design.

Torque Converter Ratios and Control Systems:

The transmissions offer multiple torque converter ratios, providing the torque multiplication needed to handle varying loads effectively. Control systems include automatic electronic, manual electric, and manual hydraulic options, offering precise control over the transmission’s performance.

Optional Features:

  • Engine-Driven PTO: Side and top mount options, capable of intermittent or continuous operation.
  • Input Retarder: Integral hydraulic, providing significant torque and power at high RPMs.
  • Cooler System: Remote mounted cooler element ensuring optimal temperature ranges.


The Allison S6610 and M6610 transmissions are designed for heavy-duty applications, providing the power and reliability needed in the oil field and heavy truck industries. Their robust construction and versatile features make them ideal for:

  • Oil Field Pumpers and Frac Equipment: High horsepower and torque capabilities ensure reliable performance under heavy loads.
  • Cementing and Drilling Operations: Precise control and robust gearing make these transmissions suitable for demanding tasks in drilling and cementing.
  • Well Service and Heavy Trucks: The transmissions provide the reliability needed for continuous operation in well service applications and heavy trucking.

Features and Benefits

Robust and Reliable:

Built from high-grade aluminum, the main housings of the S6610 and M6610 ensure durability and long-term reliability. The use of the Allison 400 series converter provides a range of stall to torque ratios, making them adaptable to various operational needs.

Precision Control:

The automatic electronic, manual electric, and manual hydraulic control systems offer operators precise control over the transmission’s performance, ensuring smooth operation and adaptability to various tasks.

Enhanced Torque Multiplication:

Multiple torque converter ratios (TC-680, TC-682, TC-683) provide enhanced torque multiplication, essential for handling diverse loads and ensuring smooth operation across different scenarios.

Efficient Cooling System:

The remote-mounted cooler element ensures that the transmission remains within optimal temperature ranges, even during extended use, preventing overheating and ensuring consistent performance.

Advanced PTO Capabilities:

Engine-driven PTOs offer side and top mount options, capable of handling up to 200 hp intermittently and 125 hp continuously, enhancing the functionality and versatility of the transmissions.

Why Choose the Allison S6610 and M6610?

The Allison S6610 and M6610 transmissions stand out due to their combination of power, versatility, and advanced features. Here’s why they excel:

Proven Performance:

These transmissions have established themselves as reliable performers in the oil field and heavy truck sectors, with a track record of durability and consistent performance in demanding conditions.

Adaptable Solutions:

With various mounting options and torque converter ratios, the S6610 and M6610 offer flexible solutions tailored to meet specific operational needs, ensuring optimal performance.

Comprehensive Support:

S&W Power Systems provides fully remanufactured, rebuilt, and dyno-tested transmissions, ensuring each unit is ready to perform under the most demanding conditions. This comprehensive support ensures reliability and reduces downtime.

Economic Efficiency:

The durability and reliability of the S6610 and M6610 translate into economic efficiency. With fewer breakdowns and less frequent maintenance, companies can save on operational costs and ensure higher productivity.


The Allison S6610 and M6610 transmissions are engineered to meet the rigorous demands of heavy-duty applications. Their combination of high power, precise control, and robust construction makes them invaluable assets for operations that require reliability and performance. Whether it’s oil field pumping, frac equipment, cementing, drilling, or heavy trucking, these transmissions deliver the power and precision needed to excel. Investing in the Allison S6610 and M6610 means choosing a solution that offers long-term reliability, economic efficiency, and unmatched performance in the toughest conditions.