ArvinMeritor unveiled its next-generation Meritor 14X tandem drive axle, built on the legacy of the company’s previous RT145 axle, at a press event March 24 in Lousville, Ky.
According to ArvinMeritor engineers, the new axle drew on that design heritage while incorporating many new technological features.
The 14X axle is the signature component member of the company’s MPG Series, which is optimized for improved total lifecycle costs, including higher productivity and increased miles-per-gallon performance.
“The 14X brings the rich heritage of its predecessor with a ‘tried and true’ design that will stand the test of time,” said Joe Plomin, truck vice president at ArvinMeritor. “New developments include a more robust and efficient inter-axle differential, the fastest ratio and widest range of axle ratios, and several other design enhancements while continuing to be the lightest axle in its class.”
To test the new design, ArvinMeritor literally hit the road with the 14X, placing it in service with fleets all across the country and eventually logging more than six million miles. Plomin said the new axle – which can be outfitted with Meritor foundation drum brakes or Meritor air discs, depending on the fleet’s preference – delivered in the field with three primary benefits:
• More robust inter-axle differential – Strength was added to the inter-axle differential, which is 20 percent larger than on the RT145 axle and can accommodate increased nominal torque generated by today’s high-torque diesel engines, up to 2050 ft.-lbs. in certain applications. The unit includes helical gear needle bearings for reduced heat and wear, upsized main differential side bearings for more capacity, and larger input shaft and rear side bearing for strength.
• Premium Amboid design now standard – The above-centerline design of the inter-axle driveline provides significant improvements, including reduced operating pressures for increased driveline life, less driveline angularity, vibration and energy loss; improved ride quality; and overall longer component life.
• Most complete range of ratios – The 14X offers the fastest ratio in the industry, 2.47:1 and all the way up to 7.17:1. The extensive range ensures coverage for nearly every application and specific engine manufacturers’ U.S. Environmental Protection Agency 2010 recommendations.
Other new key features include:
• Optional DualTrac track housing – The new optional intermediate track housing is designed to optimize the use of wide-based tires. This feature allows the use of wide-base super-single tires with the equivalent bearing life of axles equipped with dual tire configurations, while still offering convertibility back to dual tires.
• Axle breather – This helps prevent water and other contaminants from entering the carrier while keeping the lube in place.
Affected trucks include model year 2008-2018 Freightliner Cascadia and Western Star 4700, 4900, 5700 and 6900 trucks. DTNA says after hard brake applications, the brake light pressure switch may not activate the brake lights with the light application of the brake pedal.