Rule Won’t Require Overhaul of Braking Systems, Experts Say

By Sean McNally, Senior Reporter

This story appears in the Aug. 3 print edition of Transport Topics.

The National Highway Traffic Safety Administration’s decision to cut the maximum allowed stopping distance for large trucks by 30% will increase truck buyers’ costs somewhat, but will not force a widespread shift to new technology such as air disc brakes, industry groups and manufacturers said.

The new stopping distance rule, released by NHTSA on July 24, would require a loaded Class 8 truck travelling 60 miles per hour to stop within 250 feet, a sharp reduction from the current limit of 355 feet (click here for previous story).



The rule applies to new three-axle tractors after Aug. 1, 2011, and to two-axle tractors by Aug. 1, 2013.

Adapting to the new rule “should be pretty smooth because the drum brake equipment has been in use for quite a few years now,” said Jim Tipka, vice president of engineering for American Trucking Associations.

When NHTSA first proposed the rule in 2005, the agency said it aimed to cut stopping distances by 20% to 30%, but it wanted brake manufacturers to be able to meet the standard with either conventional drum or air disc brakes.

Brake manufacturers have said that in most applications, the shorter stopping distance can be met using larger drum brakes (click here for previous story).

Tim Kraus, executive director of the Heavy Duty Manufacturers Association, described the final rule as “the result of a lot of back andforth from a technical standpoint,” in part so the agency “can’t be accused of favoring any one particular product” over another.

Walt Frankiewicz, president of Bendix Spicer Foundation Brakes, told Transport Topics that now that the long-awaited rule has been published, “the industry can get on with its various options” to meet the new standard.

Frankiewicz said the company was pleased “to see that NHTSA has taken a very aggressive stance on stopping distance improvement . . . we’ve always supported the 30% reduction.”

In a statement, Joe Plomin, vice president of ArvinMeritor’s truck division, said that it was “a real benefit that truck operators are able to meet their stopping needs and the new federal stopping distance requirements without having to make significant changes to their drum brake specifications or service practices.”

ArvinMeritor’s “optimized drum brakes will meet the full compliance timeline, and we will continue to work with our OEM customers to make this new regulation transition seamless,” the company said.

Frankiewicz said Bendix Spicer has for some time projected greater use of disc brakes, and that the rule could “certainly drive an uptick in [disc brake sales] down the road.”

“In general,” he said, disc brake makers will “see a slightly higher take rate than prior to the advent of the rule.”

Tipka said that some truck configurations may shift from drum brakes to disc brakes, but that most fleets would continue to use the more familiar technology.

“I believe that the 6×4 tractor users will continue to use drum brakes, only because it is a brake that all the mechanics are familiar with,” he said. “I think we’re going to see disc brakes probably on the front end of 4×2 tractors because those seem to be a place where you really want more side-to-side stability.”

Steve Bell, air disc brake engineering manager with Bendix Spicer, said that the company believes “that we have solutions for all cases at this point.

“The challenge in front of us right now is taking very good technical solutions and making them affordable technical solutions,” Bell said.

In its rule, NHTSA said that using larger drum brakes to meet the new standard would cost $211 per vehicle, or $27 million across the industry.

However, the cost to the industry if disc brakes were used universally to meet the standard would be $1,475 per truck, or $192 million overall.

In the most likely scenario suggested by NHTSA, a combination of disc and drum brakes, the industry’s cost would be $54 million, or $413 per truck.