Bendix Commercial Vehicle Systems has made its EnduraSure-Pro sealed spring brake for air disc brakes available as a factory-installed option on all Kenworth medium- and heavy-duty models. The sealed design helps protect against moisture and contaminant intrusion, which remains the most common cause of spring brake failure in commercial vehicles.
Highlights
- Bendix EnduraSure-Pro sealed spring brake is now a factory option on all Kenworth medium- and heavy-duty truck models
- Sealed design eliminates park-side drain holes and uses a one-way check valve dust plug to block moisture and contaminants
- Power spring life extends up to five times longer than standard vented spring brake designs
- Addresses rollaway safety risk caused by broken power springs, which are difficult to detect on air disc brake systems
Sealed Design Targets Corrosion and Downtime
In standard vented spring brakes, water, dust, and aggregates can accumulate and block drain holes. This accelerates corrosion and degrades the power spring over time. Bendix addressed this by eliminating the park-side drain holes entirely. In their place, the company integrated a one-way check valve into the dust plug. As a result, air can escape while moisture and contaminants stay out.
According to Bendix, this approach delivers power spring life up to five times longer than a standard vented unit. For fleets, that translates to fewer replacements, lower roadside service costs, and reduced downtime.
Safety Implications for Air Disc Brake Systems
A broken power spring reduces the spring brake’s ability to hold a parked vehicle. On air disc brake systems, this type of failure is particularly difficult to detect compared to drum brakes. Consequently, the risk of a potential rollaway increases.
The EnduraSure-Pro design helps mitigate this risk by protecting the power spring from the corrosion that leads to breakage. Nicole Oreskovic, Bendix vice president of sales and marketing, noted that the company’s partnership with Kenworth spans decades. She said the addition of the EnduraSure-Pro to Kenworth’s available Bendix options adds value while helping lower total cost of ownership.
Engineering Features That Extend Spring Life
Beyond its sealed housing, the EnduraSure-Pro incorporates several design elements aimed at durability:
- Anti-coil clash spring design: The power spring is engineered to virtually eliminate coil-to-coil contact during compression, which can wear away protective coatings and lead to corrosion
- Greater power spring shut height: This reduces stresses on the spring and helps maintain force output over extended service periods
- Integrated wheel-end system compatibility: Bendix supplies fully integrated air disc brake systems rather than standalone components, which the company says delivers added performance
Total Cost of Ownership Considerations
Frank Gilboy, Bendix director of foundation drum brake and actuators, emphasized that the cost benefits increase with vehicle ownership duration. He noted that trailer applications see particularly strong returns. Fleets typically keep trailers longer, and equipment that sits for extended periods is more susceptible to moisture accumulation.
However, Gilboy added that fleets do not need to operate in harsh environments to benefit. While sealed spring brakes have traditionally been popular in severe-duty and off-road applications like bulk hauling, carriers of every type can realize long-term value and safety advantages.
Air Disc Brakes and Advanced Safety Systems
Gilboy also highlighted the broader role of air disc brakes in commercial vehicle safety. ADBs deliver consistent stopping performance with minimal brake fade. In addition, they support optimum performance of higher-level safety technologies, including full stability and collision mitigation systems. Protecting these systems from the consequences of failed spring brakes, he said, becomes even more important in that context.
Bendix’s EnduraSure spring brake lineup includes both standard and sealed options for drum and air disc brake applications.
For more information, visit bendix.com. Additional technical resources are available at knowledge-dock.com.
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