An accident in early 2014 has led to a recall of a fifth wheel model that allowed a semitrailer to decouple and hit two pickup trucks on an Ohio highway, killing their drivers.

Fontaine Fifth Wheel Co. said an Ohio Highway Patrol investigation found that the Ultra LT unit was not defective, but has agreed to recall about 6,800 of them and replace them at no charge to tractor owners. Fontaine will also pay for up to $100 for labor involved in a switch to a newer model, the Ultra NT, which includes a No-Slack, two-lock design.

The recalled LT fifth wheels carry part number SLTPL4000, and were manufactured from July 29, 2009 to May 27, 2013, according to an announcement by the National Highway Traffic Safety Administration. Fontaine sold them to Daimler, Volvo, Mack, Navistar and Paccar for installation on their truck-tractors.

The crash occurred about 6:30 a.m. on January 24, 2014, on a hilly, curving section of U.S. 50 east of Cincinnati, news reports said. The trailer, loaded with groceries, dropped off the tractor and slid into oncoming traffic, striking the pickups. Their drivers, Michael Brown, 43, and Shawn Wilson, 39, were killed.

Police said Michael Simpson, 62, the truck's driver, failed to properly inspect the fifth wheel’s locking mechanism and did not see that its jaws had not fully grasped the trailer’s kingpin. They said that frozen grease and lack of maintenance had prevented the jaws from locking.

Prosecutors charged Simpson with vehicular manslaughter, and he was convicted this past June. His commercial driver's license was suspended for 90 days and he got a year's probation. Civil suits against him, his company and other parties may yet be filed.

“Over time, improper coupling techniques may result in cumulative damage to the fifth wheel and its locking mechanism, which in turn may result in the locking mechanism failing to operate or to properly engage,” NHTSA’s recall announcement said. “If the fifth wheel and locking mechanism are sufficiently damaged, the locking mechanism may fail to operate as intended and the trailer may unexpectedly detach from the tractor, increasing the risk of a crash.”

Fontaine Fifth Wheel’s president, Ken Kelley, said the Ultra LT had been discontinued in 2013 as part of a “product rationalization” to reduce the number of products and parts. While the LT was in production, Fontaine made lock-related improvements and issued a technical service bulletin warning of possible problems if the fifth wheels were improperly used and not properly maintained, a company statement said.

Following the accident, “Fontaine proactively reached out to NHTSA in May 2015 to discuss conducting a field campaign to replace the remainder of the subject population of the 2009-2013 Fontaine Ultra LT fifth wheels sold in the United States in response to continued field observation of damaged fifth wheels,” the statement said. 

“Fontaine did not consider there to be a safety related defect in the units, but had decided to replace the units to provide more robust feedback to operators, to reduce the potential for operator error and to eliminate the need to continue to stock parts and repair kits for a discontinued product.“