Makers Debut Drum, Air Disc Brakes that Meet New Stopping-Distance Rule

By Jonathan S. Reiskin, Associate News Editor

This story appears in the April 4 print edition of Transport Topics.

LOUISVILLE, Ky. — Reconfigured drum and air disc brakes that meet the new federal stopping-distance rule for commercial vehicles that takes effect in August made their debut here, and one truck maker said air discs will be standard on all its Class 8 trucks.

Bendix Commercial Vehicle Systems and the newly renamed Meritor Inc. said in separate March 30 press briefings at the Mid-America Trucking Show that their products will be able to stop fully loaded rigs in less than 250 feet with tractor brakes only, marking at least a 29.6% improvement from the old federal standard of 355 feet. While brake makers are eagerly promoting the more expensive air disc models, they also said they have drum brakes with better friction material that can meet the new standard.

“We are expecting 60% growth this year over 2010 in the sale of air disc brakes,” said Gary Ganaway, a brake manager for Bendix, a division of Germany’s Knorr-Bremse Group. While European trucks are generally made with air discs, American fleet managers have generally preferred drum brakes, meaning the explosive growth would be occurring off a low base.



Peterbilt Motors Co. told reporters on the same day that air disc brakes would now be standard on the front, or steer axles of the company’s Class 8 trucks. Beyond that, discs would be available as an option on all other wheel positions.

General Manager Bill Jackson said Peterbilt made air discs standard on the company’s Model 587 highway tractor, introduced last year, and that they are a good feature for motor carriers concerned with weight issues.

Meritor Inc. — known as ArvinMeritor Inc. until March 30 — said it has made improvements on its drum models so that it can meet the new rule with versions that are weight-neutral.

Chad Mitts, a Meritor brake engineer, said his company offers a stamped steel spider, the part that holds the braking mechanism, in place of the cast iron spider in current use.

Mitts’ boss, Vice President Joe Plomin, said the company’s air discs can stop a tractor combination in 215 feet, while the new drums can do it in 225 feet.

Walt Frankiewicz, president of the Bendix Spicer Foundation Brakes joint venture with Dana Holding Corp., said the “utilization rate is about one in 20 for linehaul trucks equipped with air disc brakes.” He estimated that will “probably be twice that next year.”

Meritor’s Mitts also said his company reviewed more than 100 friction materials for the new drums and was able to come up with a new substance that contains neither copper nor lead, metals that are under scrutiny by state governments, some of which are considering regulations to ban the use of toxic friction materials.

“They would be fully compliant” with any such rules, Mitts said.

Bendix CEO Joe McAleese has long heralded the brake rule from the National Highway Traffic Safety Administration as an important event for suppliers. He said the new brakes “play right to the sweet spot” for his company, but added that Bendix is not de-pendent upon more federal regulation for business.

“We’re not relying on mandates for our technology. We always offer a direct pay-back to the fleet,” McAleese said.