Vehicle recall 78V210000 · October 3, 1978
Mack DM, DMM and 12 more models
Delays of up to about 2 seconds may exist in the brake application times to the brakes on the bogie axles in the presence of certain types of wheel speed sensor signal…
Source: NHTSA data as of September 22, 2026. Last refreshed Sep 23, 2026, 2:43 AM UTC.
- Summary
- Delays of up to about 2 seconds may exist in the brake application times to the brakes on the bogie axles in the presence of certain types of wheel speed sensor signal discontinuities or distortions that may occur as a result of sensor wire failure. This constitutes a non-compliance to federal motor vehicle safety standard no. 121, "air brake systems".
- Remedy
- Dealer will install new wheel speed sensors that incorporate improved wiring and the present bogie anti-wheel lock system will be changed to an axle-to-axle system for improved reliability.
- Notes
- Vehicle description: heavy trucks.system: service brakes; electrical wiring and connectors.consequences of defect: this delay in effective braking action could lead to anaccident under certain traffic conditions.
Recall details
- NHTSA campaign
- 78V210000
- Reported to NHTSA
- October 3, 1978
- Filed by
- MACK TRUCKS, INCORPORATED
- Owner notification
- November 7, 1978
- Vehicles potentially affected
- 19,370
- Initiated by
- the manufacturer
- Components
- Service brakes, air › Antilock › Interconnecting assembly(wiring)
Vehicles covered
As listed by NHTSA. A recall usually covers only some vehicles of each model and year, often a production date range.
- Mack DM (1977-1978): 1978, 1977
- Mack DMM (1977-1978): 1978, 1977
- Mack F (1977-1978): 1978, 1977
- Mack MB (1977-1978): 1978, 1977
- Mack R (1977-1978): 1978, 1977
- Mack RD (1977-1978): 1978, 1977
- Mack RL (1977-1978): 1978, 1977
- Mack RM (1977-1978): 1978, 1977
- Mack RS (1977-1978): 1978, 1977
- Mack RWL (1977-1978): 1978, 1977
- Mack RWS (1977-1978): 1978, 1977
- Mack U (1977-1978): 1978, 1977
- Mack WL (1977-1978): 1978, 1977
- Mack WS (1977-1978): 1978, 1977
Has your Mack been repaired?
Recalls here come from NHTSA’s records for the model and year. Not every vehicle of a model is included in every recall, and this site can’t see whether a repair has been done. Only a VIN lookup can tell you that.
NHTSA’s VIN search doesn’t show recalls that were already repaired, recalls more than 15 years old, or some small manufacturers’ recalls. A Mack dealer can also check your VIN. Recall repairs are free.