Safety is among the main benefits of air disc brakes while drum brakes “will still fill certain needs” at some fleets, an executive with Bendix Spicer Foundation Brake said.
“Shorter stopping distances, virtual elimination of brake fade and improved in-line brake stability (from left to right side) providing surer, safer stops make air disc brakes an improvement in safety over drum brakes,” Keith McComsey, the company’s director of marketing and customer solutions, wheel-end, told Equipment & Maintenance Update earlier this year. In testing using Bendix’s air disc brake system, ADB22X, at every wheel-position on the tractor and trailer at 80,000-pound GCW, “we’ve demonstrated approximately 20-foot shorter stopping distance at 60 mph,” he said. “Just increasing that to 70 mph, that stopping distance difference increased to 50 feet.”
The May-June 2018 issue of E&MU reported that not all fleets are convinced of the benefits of air disc brakes, however. But the suppliers maintain there is a growing acceptance of them for heavy-duty trucks, driven by an increase in active safety technology, such as collision mitigation and avoidance systems.
“Without further mandated reductions in stopping distances, I think we will see air disc brakes eventually becoming the typical (standard) brake utilized in North America, but I believe drum brakes will still fill certain needs,” McComsey said. “Drum brakes will continue to meet the need for larger axle ratings, certain niche applications and/or for certain fleets where the ADB cost numbers just don’t work,” he said, noting, for example, a fleet that only keeps its equipment for three years won’t be able to take advantage of the long-term total cost of ownership benefits of air disc brakes.
McComsey, in the written comments in March, said Bendix is seeing a jump in the market for ADBs from a take rate of 15% in 2016 to nearly a 25% take rate for Class 6-8 vehicles running air brake systems at the end of 2017.
Transport Topics reported on June 29 that Kenworth Truck Co. announced that Bendix’s ADB22X front and rear air disc brakes are now standard equipment on its flagship T680 on-highway truck. The Bendix brand front ADBs had been standard for several years and now the rear disc brakes are being added, TT reported.
McComsey also offered some maintenance tips. “When it comes to any brake system, they all require preventative maintenance not only to keep them operating effectively in providing continuous brake performance, but also to provide long life to the components. Air disc brakes are no different.”
The story was compiled from an interview by Contributing Writer Steve Sturgess.