Larger Differentials + Precision-Machined Gears = More Uptime

Detroit® continues to refine and expand its lineup of axles. New heavy-duty drive technology provides customers with the latest technology to help improve efficiency and performance.

Designed for higher torque applications, quieter operation and increased payload capacity, Detroit rear-drive axles are also easy to maintain, increasing your uptime and reducing your cost of ownership. Detroit's latest axle technology facilitates the use of faster axle ratios to support downspeeding.


Model 2

Available ratios 2.92 to 6.14

Model 2 Weight Ratings: 13,000 lbs to 21,000 lbs

Model 4

Available ratios 2.86 to 6.14

Model 4 Weight Ratings: 17,500 lbs to 23,000 lbs

Model 6

Available Ratos 2.28 to 5.88

Model 6 Weight Ratings: 17,500 lbs to 23,000 lbs

More Specs

Precision Machined Gears

The ring and pinion gears are machined using highly advanced power-dry cutting and grinding that result in exacting tooth profiles and ideal gear mesh—so precise, in fact, that the ring and pinion gears do not require pairing. These sophisticated processes render perfectly matched gearing to ensure more efficient power transmission, longer durability, quiet axle operation and enhanced driver comfort.




Single Rear Axle Explorer

Click through the tabs below to learn more about the Single Rear Axle features and benefits. 

Larger Differential

Larger differential components add stability and increase durability.

Brake Compatibility

Compatible with all brake systems offered by Freightliner Trucks, Western Star, Thomas Built Buses and FCCC.

Ground Clearance

Model 2 features increased ground clearance due to smaller bowl to help avoid obstacles.

Precision-Machined Gears

Precision-machined gears optimize the power flow and reduce noise.

Model Options

Designed for construction, distribution, dump, fire and emergency, government, motor home, oil & gas, refuse, and regional. 

M2 112 Plus
The Freightliner M2 106 Plus truck on a road in front of a green field.
M2 106 Plus
114SD Plus
108SD Plus
Western Star
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Integrated Detroit Powertrain


The Integrated Detroit® Powertrain delivers the performance and dependability you need to run your business efficiently. Detroit has designed, engineered and manufactured the engine, transmission and axles to work together seamlessly, providing the optimal powertrain solution for your business needs. The integrated Detroit Powertrain is available in the Freightliner Cascadia®.

Steer Axle

  • Numerous Steer Axle Advantages: Detroit steer axles offer rugged strength in a lightweight package, and integrate optimally with the other components. They are designed for the life of the axle, with multiple ratings available for tailored weight distribution.
  • Superior Maneuverability: The Detroit Powertrain's state-of-the-art steer axles provide a 55-degree wheel cut for remarkably nimble maneuvering. 
  • Needle Bearings Improve Durability: With needle bearings instead of bushings, they won't damage the king pins, and offer increased durability.


Tandem Rear Axle

  • New Axles Designed for Fuel Economy: To provide optimum efficiency and performance, the Detroit® Powertrain includes an all-new axle specifically designed to integrate with the downsped DD13® Gen 5, DD15® Gen 5 and DT12®, resulting in rock-solid reliability and durability.
  • Faster 6x4 Axle Ratios: The 6x4 configuration is available for applications requiring 4-wheel drive and superior traction. A variety of faster axle ratios are available, ranging from 2.41 to 2.16.
  • Faster 6x2 Axle Ratios: The 6x2 configuration boasts a 2.28 ratio, allowing the DD15 Gen 5 to turn lower RPMs with the truck cruising at the same speed. It pairs perfectly with the low RPM torque curve and direct drive transmission. This means it can cruise in top gear longer, for better fuel efficiency.
  • Lighter 6x2 Axle: The 6x2 axle configuration incorporates a non-driven tag axle on the tandem, reducing total weight (by 380 lbs) and the number of moving parts, delivering better fuel economy.
  • Axle Lubrication Management (ALM2): The tandem rear axles feature an optional axle lubrication management 2.0 (ALM2) system that regulates the oil level at the ring gear and friction-loss optimized pinion bearings to reduce friction and parasitic loss, extending gear life and further improving fuel efficiency.


  • Engine Compliance: Detroit provides a wide range of new vehicle engines compliant with EPA, CARB emissions, GHG, and OBD requirements. Please consult your local dealer to ensure the selection of a product that meets your specific needs.
  • Downsped Engines = Improved Fuel Economy: The DD13 and DD15 downsped ratings 425/450/455 and 1750 lb/ft rating deliver greater horsepower and torque at lower RPMs, keeping your truck in top gear longer while cruising at more efficient engine speeds. Lower engine speeds reduce the number of fuel injections, dramatically improving fuel economy.
  • Six-Blade Engine Fan: The six-blade fan reduces power draw without sacrificing cooling capabilities.


  • Integrated Communications Benefits: The DT12® transmission links engine to axles, and communicates with the DD13 Gen 5  and DD15 Gen 5 on an integrated electronics network to share damage-reducing information such as clutch overloading and driveline protection.
  • Super-Finished Gears: Tightly-spaced 12-speed gearing, now with "super-finished" gears in the new DT12 available for the new Cascadia and Western Star® 5700XE, improves low-speed maneuverability, making the Detroit Powertrain not only strong and efficient, but also smooth and safe to operate as well.
  • Intelligent Powertrain Management (IPM): The DT12 uses GPS technology and information from a topographical map to manipulate both engine and transmission functions, taking advantage of the truck's surroundings. IPM6 refines the parameters of this technology, making the truck even more capable of utilizing its surroundings efficiently.
  • Transmission Benefits: The DT12's direct drive and over drive gearing, along with eCoast, are integrated with the downsped engine — which now idles at a lower 500RPM when off-throttle — for optimized fuel economy.



  • 1-Box®: The 1-Box is a complete aftertreatment emissions system that combines the SCR catalyst, the Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF) and Diesel Exhaust Fluid (DEF) all into one simple component.


Brochures and Spec Sheets

Detroit Powertrain Product Overview Guide (Freightliner New Cascadia)

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