A faulty brake valve produced by Bendix Commercial Vehicle Systems has been installed on as many as 60,000 Navistar Inc., Paccar Inc. and Volvo Group heavy-duty vehicles that are now in service.

The flawed valve also has halted or delayed delivery of an unknown number of trucks that are in various stages of production.

News of the problem was made public Feb. 1 during a quarterly Navistar meeting with stock analysts. Navistar did not disclose the number of vehicles affected.

Navistar halted delivery of heavy-duty trucks with the valves on Jan. 20, a move that affected 40% of its total production, CEO Daniel Ustian told Light & Medium Truck’s sister publication Transport Topics. Volvo now has resumed deliveries after postponing them on Jan. 19, spokesman Brandon Borgna said.

Paccar has recalled 15,932 of its 2012 - 2013 model-year Kenworth and Peterbilt trucks equipped with the components due to concerns that the brakes could engage and possibly overheat when exposed to extremely cold conditions.