Campaign 21V-856

Machining defect may cause pressure to build in the power steering pump and break the shaft seal, resulting in a loss of power steering assist

Defect summary

Mack Trucks, Inc. (Mack) is recalling certain 2021 Granite and LR vehicles. A machining defect may cause pressure to build in the power steering pump and break the shaft seal, resulting in a loss of power steering assist.

Consequence

A loss of power steering assist increases the risk of a crash.

Remedy

Dealers will replace the power steering pump, free of charge. Owner notification letters were mailed on December 10, 2021. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0432.

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.

Source: NHTSA ODI recalls file, campaign 21V856000. Text as published by NHTSA.

Vehicles covered

2 product lines are covered

Owner complaints filed with NHTSA about steering on these vehicles: 0, of which 0 involved a crash, fire, injury or death. Complaints are not verified by NHTSA.

Vehicles covered by campaign 21V-856
Make	Model	Model years	Complaints on this component
Mack	Granite (GR)	2021	0
Mack	LR	2021	0

Source: NHTSA ODI recalls and complaints files. Equipment, tire and child-seat campaigns list products, not vehicles.

Investigation

No NHTSA investigation is linked to this recall

Most recalls are started by the manufacturer. This one lists "Manufacturer" as its origin.

Before the recall

2 service bulletins on this component came first

Distinct manufacturer communications on the same component group, make, model and model year in the 24 months before the report date.

Source: NHTSA manufacturer communications file.

Service bulletins

26V-509 Aug 6, 2026
Steering gearbox fasteners may loosen
25V-521 Aug 11, 2025
Dynamic steering and oversteer guidance feature may malfunction and cause a loss of steering control
24E-065 Aug 5, 2024
Tie rod assemblies may contain ball studs that have been incorrectly heat-treated, which can cause them to break, and possibly result in tie rod…
24V-504 Jul 2, 2024
Tie rod assembly ball stud could have been improperly heat treated and can fail
24V-398 Jun 4, 2024
Drag link may contain an improperly heat-treated ball stud that can fail, resulting in a sudden loss of steering control
23V-899 Dec 26, 2023
Steering gear assemblies may have been assembled incorrectly with fewer recirculating balls than are required, which may result in a loss of…