Eaton has announced its Vehicle Group is celebrating 50 years of MLocker differential production. The mechanical locking differential provides drivers with best-in-class traction without the need for pushbuttons, shift knobs, or other driver intervention, and is applicable to vehicles with both internal combustion engines and electrified vehicles (EVs).

“We’re happy to celebrate this important milestone for the MLocker differential, which is built on the success of its predecessor, our popular Posi differential,” said Mark Kramer, business unit director, torque control products, Eaton’s Vehicle Group. “The unique design and proven quality of the MLocker differential have made it the differential of choice for global full-size pickups and sport-utility vehicles, and even a recently launched electrified urban truck in the Asia-Pacific region.”

Driving original equipment innovation

Utilizing a self-contained, automatic engagement mechanism, the MLocker differential engages in low-traction situations when a wheel speed difference (compared to the other rear wheel) of 100 revolutions per minute (RPM) or greater is detected. Automatic locking takes less than a fraction of a second, improving traction and providing the driver with increased safety and confidence when traveling on wet or icy roads, gravel, mud, and dirt. The MLocker differential is also compatible with existing anti-lock brake and vehicle stability systems, which simplifies OEM integration.

During normal driving conditions, the MLocker differential functions as a light-bias, limited-slip differential. When a low-traction situation occurs that causes a wheel speed difference, a flyweight mechanism opens to engage a latching bracket, triggering a self-energizing clutch system until both axles turn at the same speed (full lock), thereby preventing further wheel slip. Unlocking occurs automatically and the differential resumes normal operation.

The MLocker differential has undergone modifications over its long production run, but the foundational design and concept have remained constant.

“Functionally it’s the same design, but we have made a lot of improvements over the years. Our initial concept has weathered the test of time, although it’s been consistently improved to meet the needs of the industry,” said Keith E. Morgensai, an engineering specialist who has been involved in MLocker differential engineering and evolution for more than 40 years.

“It’s deceptively simple, but there is an awful lot of engineering that went into its development,” Morgensai said.

Since launching the MLocker differential, Eaton’s Vehicle Group has continued to add to its differentials portfolio that offers solutions for all user profiles.

Eaton’s complete line of differentials now includes:

• Detroit Locker differential – A fully automatic locking differential that provides ultimate traction for mild to extreme vehicle applications. It is uniquely engineered to keep both wheels in drive mode, even if one wheel lifts off the ground.
• Detroit Truetrac differential – A helical-gear performance limited-slip differential that maximizes wheel traction and enhances driving and handling characteristics.
• ELocker differential – A highly engineered unit that allows maximum driveline flexibility. Users can switch from a fully open to a fully locked axle at the touch of a button. The forged case and four-pinion gears provide added strength and capability.
• InfiniTrac differential – An electronically controlled, limited-slip differential that provides optimized vehicle performance at any speed and traction condition.
• Posi differential – A limited-slip differential that automatically prevents wheel slip before it can start. It easily integrates into most axle designs and is tunable for application requirements.

Eaton also recently announced its Torque control systems business has launched an extensive lineup of specialized differentials for EVs with comparable performance to differentials for traditional internal combustion engine vehicles.

The passenger vehicle market is increasingly transitioning to EVs, and Eaton has the expertise and experience to provide the solution EV manufacturers need.

Eaton’s Traction Control family of differentials can provide improved traction in adverse conditions, such as snow and mud, and improved stability while trailering. As a global supplier, Eaton has extensive knowledge of vehicle dynamics and safety standards, as well as decades of experience working with global automotive manufacturers to integrate differentials into new vehicle platforms, including EVs. This technology is an example of how Eaton is progressing toward achieving its 2030 Sustainability Targets. By 2030, the company aims to reduce emissions from its solutions and throughout its value chain by 15%.

“Our years of experience producing industry-leading differentials allows us to provide our customers with a differential solution to meet their every need,” Kramer said. “The success of the MLocker differential was just the beginning of our journey to become a global supplier of differentials.”

Learn more about Eaton’s complete line of differentials.