Vehicle recall 21V720000 · September 16, 2021

2020-2021 Peterbilt 520

The quick release valve on the rear brake signal hose may be missing.

Source: NHTSA data as of September 22, 2026. Last refreshed Sep 23, 2026, 2:43 AM UTC.

Summary: PACCAR Incorporated (PACCAR) is recalling certain 2020-2021 Peterbilt 520 vehicles. The quick release valve on the rear brake signal hose may be missing. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 121, "Air Brake Systems."
Consequence: A missing quick release valve cannot ensure correct rear brake release timing, increasing the risk of a crash or injury.
Remedy: Dealers will inspect the vehicles for a missing quick release valve, and install one if necessary, free of charge. Owner notification letters were mailed on October 7, 2021. Owners may contact PACCAR's customer service at 1-940-591-4220 (Peterbilt). PACCAR's number for this recall is 21PBK.
Notes: Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to www.nhtsa.gov.

Recall details

NHTSA campaign: 21V720000
Reported to NHTSA: September 16, 2021
Filed by: PACCAR Incorporated
Manufacturer campaign: 21PBK
Owner notification: October 7, 2021
Vehicles potentially affected: 15
Initiated by: the manufacturer
Components: Service brakes, air

Recall 21V720000 on nhtsa.gov, with the manufacturer’s documents

Vehicles covered

As listed by NHTSA. A recall usually covers only some vehicles of each model and year, often a production date range.

Peterbilt 520 (2020-2021): 2021, 2020

Has your Peterbilt been repaired?

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