Bendix Works to Correct Defect, but Date for Valve Fix Uncertain

Officials of brake manufacturer Bendix Commercial Vehicle Systems said they are wrestling with the challenge of manufacturing and distributing replacement parts for a defective valve that could cause braking problems, which prompted federal and heavy-duty truck manufacturer recalls.

“We’re working on this now,” said Bendix spokeswoman Barbara Gould. “We have a team in place, and we’re making as many as we can. They’re working very long hours to bring a resolution to this as quickly as possible,” although she could not specify a precise date.

The component, a newly re-designed ATR-6 traction relay valve, is part of sophisticated vehicle safety and stability systems. In a few cases in subzero temperatures, the defective part has caused spontaneous braking, which in turn has led to vehicle fires.

A Bendix manager said 85% or more of the 131,221 valves in question are on more than 64,000 commercial vehicles, most of them heavy-duty U.S. and Canadian trucks, but some are on Class 5-7 medium-duty trucks, intercity buses and stocked at truck-part distributors.

The valves are not used on Bendix’s basic foundation brakes for trucks, and there are one or two valves per vehicle.

Five heavy-duty truck makers are affected: Kenworth Trucks; Peterbilt Motors; Navistar International; Volvo Trucks and, to a lesser extent, Mack Trucks. Freightliner and Western Star units use a different supplier and are unaffected.

Bendix said it is “finalizing the logistics” on manufacturing and distributing kits for a permanent solution.

“We’ll replace the top cover of the traction relay valve, which means you have to remove four bolts, perform the verification process and replace them,” said Kevin Romanchok, a Bendix product line director, describing the permanent repair procedure.

Bendix, based in Elyria, Ohio, described a temporary fix shortly after the problem was revealed Feb. 1 during a Navistar meeting with stock analysts (2-6, p. 1).

The temporary solution involves using a rubber plug to fill a hole, but that removes some of the functionality of the safety systems.

The traction valves are used with Bendix systems for active cruise control with braking — Wingman ACB and Wingman Advanced — and its electronic stability program — Bendix ESP.

Bendix, a division of the German Knorr-Bremse Group, notified truck makers of the problem on Jan. 19, and told the National Highway Traffic Safety Administration. Bendix filed formally with NHTSA on Jan. 26.

According to NHTSA filings, 57,272 U.S. vehicles are affected. Manufacturers said additional trucks in Canada had the defective valves.

Volvo Trucks had the most with 22,383 trucks manufactured be-tween Dec. 2, 2010, and Jan. 18 of this year, plus more than 3,500 trucks in Canada.

Mack Trucks made just 11 trucks with the Bendix valves.

Navistar made 18,946 U.S. trucks and 1,738 in Canada with the valves, Peterbilt had 9,946 U.S. trucks and 350 in Canada, while Kenworth had them on 5,986 U.S. trucks and 1,084 in Canada.

A spokeswoman for Daimler said Freightliner and Western Star use comparable systems made by Meritor Wabco.

Bendix said the defective ATR-6 valve was first produced Dec. 2, 2010, and they started appearing on new trucks later that month.

Suppliers and truck makers have long said there is constant market pressure to produce lighter weight, durable parts more efficiently.

Bendix told NHTSA the design change on the new ATR-6 involved “eliminating four small internal ribs in the cover assembly and a material change made to a rubber ball seal in the solenoid.”

When subjected to temperatures of less than zero degrees Fahrenheit, the rubber ball — which gets stiffer in cold weather — can allow air to flow, thereby causing unwanted braking.

Paccar Inc. Counsel Michael Walton told NHTSA that a Peterbilt investigation conducted after the Bendix notification found six customer complaints from Canada and the Great Lakes states.

“Two of the incidents may have resulted in vehicle fires. There were no reported incidents of a crash of loss of vehicle control. Kenworth conducted a similar investigation and did not discover any complaints related to this condition,” the Paccar report said.

Bendix spokeswoman Gould said the company manufactures the valves domestically at several sites, but did not specify the factories. The Bendix website lists four U.S. plants: Bowling Green, Ky.; North Aurora, Ill.; Huntington, Ind., and Del Rio, Texas.

Heavy-duty U.S. truck sales grew strongly in 2011, increasing nearly 60% over 2010 levels. This year, manufacturers and analysts estimate they will grow further still, although the percentage rate is expected to slow. Therefore, Bendix will have to manufacture replacement kits for all of last year’s production, plus valves for this year’s new trucks.

For U.S. trucks made since December 2010, most of the repairs should be performed under manufacturer’s warranty in dealerships, said Richard Witcher, chairman of American Truck Dealers. An International dealer in Walpole, Mass., Witcher said Navistar did not brief its dealers on this at the recent ATD conference in Las Vegas. In general, though, Witcher said work related to NHTSA recalls is usually paid for by the manufacturer.

As few Mack units are involved. Mack dealers did not get a briefing at ATD, but Volvo and Kenworth dealers did hear about the valves at their make meetings.

Wheeling, W.Va., Volvo dealer Ron Remp said he heard about the issue from Ron Huibers, Volvo Trucks’ president of North American sales and marketing. Remp said there was a delay in shipping trucks from Volvo’s Dublin, Va., plant but that shipments have resumed.

Virginia Kenworth dealer Jim Hartman said Kenworth is shipping trucks with the affected valves because the manufacturer does not want to stockpile the vehicles at its Chillicothe, Ohio, and Renton, Wash., plants. Hartman said dealers will have to replace the valves before delivery as the kits become available.