MARKHAM, Ont. – New stopping distance requirements being introduced in the US in August may be the catalyst for the widespread shift towards air disc brakes, according to speakers at this year’s Canadian Fleet Maintenance Seminar.

However, Scott Deslippe, national sales manager with Express Brake International, pointed out they will cost a premium. Deslippe did some cost comparisons prior to his presentation at CFMS and concluded the initial cost of equipping a tractor with air disc brakes could be as much as $3,000. Then there is technician training required and fleets that operate in remote areas may not yet be convinced that mechanics in those areas are well equipped to work with disc brakes, he pointed out.
A drum and shoe replacement can be done for as little as $125-$175 with a complete system rebuild costing about $340 to $400, Desplippe noted. Replacement costs on air disc brakes on the other hand can run as high as: $200-$325 for pads; $550-$600 for rotors; $750-$850 for calipers with a complete rebuild costing up to $1,700.

“So there’s obviously more cost involved with disc brakes but you’re getting better performance and longevity from them as well,” Deslippe added, not wanting to slam the brakes on the adoption of discs.

Paul Reitz, general sales manager of Peterbilt Ontario Truck Centres, was also at CFMS, singing the praise of today’s air disc brakes, which Peterbilt recently announced is now standard on the front axle of all its Class 8 models. Reitz said Peterbilt’s decision to be the first to transition to disc brakes as standard equipment was made to comply with the new stopping standard coming this summer.

“Peterbilt decided a while ago when producing the Model 587 that it didn’t want to just meet that goal but surpass it,” Reitz said of the new stopping requirements.

In addition to surpassing legislative requirements, Reitz said Peterbilt is confident there’s good value in disc brakes for end users.

“We think there’s value in it,” he said. “There’s a lower cost of maintenance, they’re safer, easier to maintain and lighter in weight.”

Reitz pointed out they’re resistant to brake fade which is important for Canadian operators who routinely traverse the Rocky Mountains. He also noted new aerodynamic tractors require greater stopping force as they have less wind resistance slowing them down while braking than classic-styled trucks did in the past.

Other benefits Reitz discussed included: Simplification (the same caliper, rotor and pads can be used on all wheel-ends of a tractor-trailer equipped with disc brakes); maintenance (no lube is required and the caliper is sealed for life); service times (it takes 25% longer to replace shoes than pads); reduced air demand (disc brakes require 33% less air to function, he noted); and reduced warranty claims (disc brakes have a warranty claim rate of less than 200 parts per million – far less than drum brakes, he noted).

Reitz said a 6×4 tractor can weigh 260 lbs less when fitted with disc brakes and service intervals are 20-100% greater than drums.

He also said some customers are doubling brake life when switching to discs and braking accuracy is improved.

The left-to-right braking variance can be as much as 30% on S-cam brakes and about 10% on discs, he pointed out, giving the vehicle a passenger car feel under braking and providing better straight line stopping.

“We think this is the solution that best suits where we needed to go,” Reitz said of Peterbilt’s decision to offer disc brakes as standard equipment.