The Shift Toward Automated Manual Transmissions

Cummins is widely recognized as a titan in the diesel engine industry, powering everything from heavy-duty pickups to massive semi-trucks. Interestingly, the company also produces its own line of transmissions, though these are designed for specific commercial purposes. As the transportation industry moved away from traditional manual gearboxes in the early 2000s, automated manual transmissions (AMTs) gained significant traction. A key milestone in this shift was Volvo’s 2001 introduction of the I-shift AMT, which grew from a niche option to commanding 95% of Volvo's transmission sales by 2021. Recognizing this market trajectory, Cummins partnered with Eaton in 2017 to launch its own series of AMTs.


The Cummins-Eaton Lineup: Built for Size and Power

The joint venture between Cummins and Eaton has yielded two primary product lines: the Endurant HD and Endurant XD. These units are engineered for high-demand commercial environments, which makes them fundamentally incompatible with the dimensions and requirements of a standard consumer pickup truck.

  • Endurant HD: Designed for efficiency in on-highway transport, featuring 12 forward gears and three reverse gears.
  • Endurant XD: Built for more rigorous, demanding applications, offering 18 forward gears and three reverse gears.

Why Pickup Trucks Use Different Hardware

For context, the most robust Cummins-powered consumer pickup trucks, which utilize the 6.7-liter turbo-diesel inline-six engine, are equipped with an eight-speed automatic transmission sourced from ZF. Compared to the massive AMTs designed by the Cummins-Eaton partnership, these consumer-grade transmissions are much more compact and specifically tuned for light-to-medium-duty pickup performance.


The Future of Commercial Shifting

The popularity of AMTs stems from their ability to automate the clutch process. Instead of a driver-operated pedal, an ECU manages the clutch via electro-hydraulic systems. This technology significantly reduces driver fatigue, especially when navigating a transmission with 18 distinct gears.

«As of 2022, the Eaton-Cummins collaboration has focused on expanding into specialized sectors like logging and oil field trucking,» according to reports on the partnership. While these industries historically favored traditional manual gearboxes for precise control, the industry expects that a new generation of drivers entering the workforce will accelerate the transition toward fully automated systems.