Mack Trucks Inc. is recalling about 22,000 refuse trucks because the parking brake can fail and cause a rollaway. The company reported five crashes with one injury related to the issue that affects all of the recalled TerraPro models from 2008 to 2022.
Affected trucks are 2008 to 2019 TerraPro (MRU) and 2019 to 2022 TerraPro (TE) models. Mack told the National Highway Traffic Safety Administration that 100% of the 21,641 trucks could have the condition.
A worn park brake control valve with an internal leak may cause air to pass through and out the exhaust port when the park brake is applied. Under certain conditions, the internal leak combined with an exhaust hose may create excessive back pressure, causing the parking brake to release unexpectedly, according to Mack’s filing with the NHTSA.
This park brake control valve wear-out condition may go undetected by the driver because the sound is muffled by the exhaust pipe configuration.
According to a chronology in Mack’s Part 573 report to the NHTSA, the company learned of a Mack MRU with the condition in May 2019. In April 2020, the agency opened a preliminary evaluation based on a complaint filed by a large fleet operator that had experienced four rollaways.
Panicked driver jumps from moving vehicle
In one incident, a vehicle rolled more than 328 feet and crashed into a parked car and a residential structure, causing more than $150,000 in property damage, according to the NHTSA preliminary evaluation. Another vehicle rolled away and crashed into several other refuse trucks parked at the depot.
The reported injury incident occurred when a driver dumped a load of refuse at a landfill, pulled into the clean-out area, set the parking brakes, locked out the main battery disconnect and went into the rear body to perform normal clean-out duties.
While inside the rear body, the driver reportedly heard the sound of rushing air, the parking brakes reportedly released and the truck began to roll away. Panicked, the driver jumped out of the moving vehicle and broke his ankle, which later required surgery. The truck came to rest approximately 164 feet away against a dirt berm.
Mack, which is part of Volvo Group North America, contended until Aug. 10, 2020, that the issue was not a safety defect. A little more than a year later, on Aug. 16 this year, the Mack sales team heard of another report involving a 12-year-old rear load packer garbage truck. With two consumer complaints, three field reports and five reports involving a crash and/or injury, Mack decided on a recall on Dec. 9.
A stop delivery for new trucks was issued on Dec. 6. The exhaust tube and fitting are being removed from new trucks. On recalled trucks, the exhaust tube and fitting will be removed from the valve at no charge to the owner.
Dealers were told of the recall last Friday. Owners will be notified on Feb. 4, 2022. The NHTSA recall number is 21V-953.