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New, Expanded Hendrickson Suspensions Available on New Western Star
Hendrickson debuted the Haulmaax EX suspension as part of its premium rear suspension portfolio included in the chassis enhancements of the new Western Star 49X, as well as the expansion of Ultimaax and Primaax EX.

A trio of tough Hendrickson suspensions will be available on the new Western Star 49X.
Photo: Hendrickson
Hendrickson debuted the Haulmaax EX suspension as part of its premium rear suspension portfolio included in the chassis enhancements of the new Western Star 49X, as well as the expansion of Ultimaax and Primaax EX.
With the 49X introduction, Hendrickson also debuts its next generation heavy-duty rubber suspension, Haulmaax EX. To address the growing demand for rubber suspensions across all vocational applications, this suspension is optimized to provide increased site rating, expanded capacity ranges and improved durability, according to Hendrickson.
“Customers today expect more out of their vocational suspensions, and Haulmaax EX exceeds those expectations by expanding on the capabilities of the current Haulmaxx design with up to a 70,000-pound site rating for the 46,000-pound-capacity suspension,” said Ashley Dudding, director of engineering for Hendrickson Truck Commercial Vehicle Systems, in a release. Haulmaax EX offers capacities of 40,000 pounds, 46,000 pounds and now 52,000 pounds.
“Hendrickson utilized our industry-leading analysis and validation techniques to ensure Haulmaax EX would meet these rigorous demands, minimize maintenance requirements and deliver the lightest weight vocational suspension on the market,” added Dudding.
The 49X will also offer Hendrickson’s Ultimaax severe-duty rubber suspension for more extreme applications, as well as Primaax EX, Hendrickson’s severe-duty vocational air suspension for applications requiring the softer ride of an air suspension but still demanding rugged durability.
Ultimaax is available in capacities of 52,000, 60,000 and 70,000 pounds and delivers enhanced stability, handling, and ride quality even in the severe-duty environments where vehicles encounter harsh and unexpected ground conditions, according to Hendrickson. The integration of Hendrickson's walking (equalizing) beam technology, with its patented progressive rate spring, provides a balance of loaded stability and unloaded ride quality.
Primaax EX is designed specifically for the demands of vocational, severe-service, and heavy-haul applications. The system features a robust structural design optimized for stability, handling and ride, resulting in higher driver comfort and less premature wear on expensive truck and body equipment, according to Hendrickson. Initially, the new Western Star will feature Primaax EX in capacities of 46,000 and 52,000 pounds, with expanded capacities coming soon.
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