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Axles Axles

S38/40 Series Axles

Available in both single and tandem configurations, Mack drive axles are the clear choice for improved performance, greater durability, increased fuel efficiency and a smooth, quiet ride.

  • 1.5% fuel economy improvement
  • Assembled in the USA
  • Capacity: 38,000 and 40,000 lbs.
  • Axle Creep Rating: 60,000 lbs.
  • Gross Combination Weight Rating: 125,000 – 180,000 lbs.

  • Straight Driveline

    A smoother, more powerful drive

    Using a prop shaft angle of two degrees or less drastically reduces driveline angles, reducing vibration and parasitic loss. Mack’s driveline design offers a quiet ride with less maintenance.

    • Steel Construction

      Superior engineering

      Built from fabricated steel, these axles feature strengthened suspension joint clamp integrity and squared-off corners to form a tighter, longer-lasting connection. Suspension brackets use set screws that are welded in place to boost bracket-to-axle weld joint integrity.

    • Dual-Reduction Architecture

      Smart and strong

      Spiral and helical gears significantly reduce stress and gear face pressure through the carriers. The spiral bevel gears provide rolling friction instead of the sliding friction, reducing frictional power loss.

    • Improved Fuel Efficiency

      Mack’s drive axles are optimized for highway applications to increase the fuel efficiency of your truck by 1.5% over industry-standard axles.

    • Complete Integration

      Fully integrated with Mack’s MP® engines, transmissions and suspensions, this complete powertrain is designed to work together seamlessly for better efficiency.

    • Uptime by Design

      The S40 axle housings have tighter tolerances and fewer joints for greater reliability and longer life. The bowl cover is seamlessly integrated into the housing for more durability and to keep dirt and debris from damaging components.

    • Maintenance Intervals

      +

      mDRIVE™

      Normal Duty

      Greater than 6 mpg Less than 39L/100km

      Heavy Duty

      Greater than 5 mpg Less than 50L/100km

      Severe Duty

      Less than 5 mpg Greater than 50L/100km

      Transmission oil and filter (Replace)

      Oil quality: Mack Transmission Oil 97318*

      Miles

      500,000

      Not Allowed

      Km

      800,000

      Not Allowed

      Hours

      60 months

      Not Allowed

      mDRIVE™; mDRIVE™ Severe Duty and mDRIVE™ with Crawler Gears

      Transmission oil and filter (Replace)

      Oil quality: Mack Transmission Oil 97319*

      * Approved oils only, lists can be made available

      Miles

      500,000

      250,000

      Km

      800,000

      400,000

      Hours

      60 months

      2500 h

      T300 SERIES TRANSMISSION

      Highway Standard and Extended Oil (Replace)

      Miles

      Std: 250,000 / Ext: 500,000

      -

      Km

      Std: 400,000 / Ext: 800,000

      -

      Hours

      Std: 24 months / Ext: 36 months

      -

      Vocational Standard and Extended Oil (Replace)

      Miles

      -

      Std: 40,000 / Ext: 80,000

      Km

      -

      Std: 64,000 / Ext: 128,000

      Hours

      -

      Std: 12 months / Ext: 12 months

      AXLES

      Rear Axle Oil (Replace)

      Miles

      500,000

      80,000

      Km

      800,000

      125,000

      Hours

      36 months

      12 months

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