PACCAR Incorporated (PACCAR) is recalling certain 2026-2027 Peterbilt 579 and 2027 Kenworth T680 tractors. The trailer air connection quick release (QR) valve in the air brake system may have been incorrectly installed, which can cause the trailer to become unstable after the driver applies the brakes. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 121, "Air Brake Systems."
An incorrectly installed quick release valve that does not function properly can increase the risk of a crash.
Paccar inspected and reinstalled the valves, as necessary, free of charge. All affected tractors have been repaired and therefore no owner notification letters are necessary. Owners may contact Peterbilt's customer service at 1-940-591-4220 and Kenworth's customer service at 1-425-828-5888. PACCAR's number for this recall is 26PACC.