NHTSA recall 21V684000
NHTSA advises: do not drive until the repair is done.
A recall listed here may apply to a vehicle of this year, make and model. Only the manufacturer can say whether it applies to one vehicle: check the VIN with the official lookups.
| Published by | NHTSA (United States) |
|---|---|
| Campaign number | 21V684000 |
| Manufacturer's number | SC0429 |
| Manufacturer | Mack Trucks, Inc. |
| Reported | 2021-09-01 |
| Owners notified | 2021-09-13 |
| Component | SERVICE BRAKES, HYDRAULIC:PEDALS AND LINKAGES |
| Units potentially affected | 2823 |
| Part numbers | 21400412 - Clevis Pin; 2509281 Cotter pin |
| Report | Annual report 3, for 2025 quarter 3 to 2026 quarter 2 |
|---|---|
| Filed with NHTSA | 2026-07-01 |
| Vehicles in the campaign | 2823 |
| Reported remedied | 2778 (98%) |
| Reported unreachable | 0 |
| Reported removed | 0 |
These are the manufacturer's totals for the whole campaign at the end of 2026 quarter 2, as filed with NHTSA. They do not say whether one vehicle has been remedied: check the VIN with the official lookups. The reports are from data as of 2026-10-19.
What is wrong
Mack Trucks, Inc. (Mack) is recalling certain 2020-2022 Mack MD vehicles. The cotter pin that retains the brake pedal clevis pin may not have been properly installed, which could result in an unsecured brake pedal.
What can happen
An unsecured brake pedal can cause a loss of braking ability and increase the risk of a crash.
The remedy
Owners are advised to not drive their vehicles until the remedy has been performed. Dealers will inspect the cotter pin installation and repair it as necessary, free of charge. Owner notification letters were mailed on September 13, 2021. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0429.
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.
| 2020 MACK MD | |
|---|---|
| 2021 MACK MD | |
| 2022 MACK MD |
A vehicle with no link is not in this site's catalog, which covers cars, multipurpose vehicles and trucks by model year. The campaign is from data as of 2026-10-19.
Bulletins for the same vehicles and component
| CBR 407 072025 | 2025-08-04. Service bulletin. CBR - To correct the MID136 SID 66 FMI 7 fault code the latest Bendix VCP file will need to downloaded. |
|---|---|
| CBR-407 202409 | 2024-10-03. Service bulletin. CBR: To correct the MID136 SID 66 FMI 7 fault code the latest Bendix VCP fi le will need to be downloaded. |
| KC-2140 | 2022-12-05. Service bulletin. Mack Chassis - P05E662 Park brake Sensor/Switch Circuit Range/Performance, Signal Compare failure - Diagnostic Instructions - US21+OBD21 Emissions |
| SLM22-004 | 2022-05-06. Service bulletin. Service Literature Published and Released in April, 2022 |
| KC-361 | 2022-02-04. Service bulletin. Mack Chassis - Drive Axle Brake Chamber Rubbing Frame Or Brake Drum - Vehicles Built Between 7 July 2014 And 23 August 2019 |
| KC-286 | 2022-01-06. Service bulletin. Mack Chassis - FSB 563-008 Plugs, Pressure Protection Manifold - New Brass Plugs For Noregon Pressure Protection Manifold (PPM) |
A bulletin is the manufacturer's note to its dealers. It is not part of this recall.