More medium- and heavy-duty trucks have been recalled due to a potentially faulty ball stud in tie rods or drag links after a third-party supplier inadvertently supplied experimental parts that used an unapproved heat-treating process. Recalls from two truck makers now total nearly 8,000.

In June, Paccar recalled nearly 3,900 medium- and heavy-duty trucks with diesel powertrains for a steering issue that could cause a loss of control. That number recently grew to 7,400.

In addition, Navistar has now recalled more than 500 International trucks due to incorrectly heat-treated ball studs from the same third-party supplier, USK International.

USK mixed ball studs with an unvalidated heat treat process into normal production flow.

Ball studs that have been incorrectly heat-treated can fracture. If the ball stud fractures, the driver may experience a loss of steering and reduced vehicle control, which may increase the risk of a crash.

So far it appears that the faulty ball studs have potentially made their way into Dana, Meritor, and Paccar components.

Navistar Recalls More than 500 International Trucks

More than 500 International trucks have been recalled due to the potentially faulty ball studs. Navistar estimates 20% of the recalled trucks have the defect.

The recall, dated July 26, affects certain 2025 model year International HV, HX, LT, MV, and RH vehicles.

Certain ball studs supplied to Meritor by a third-party supplier, USK International, which Meritor incorporated into certain steer axles and replacement tie rod assemblies, did not meet case hardening specifications, and there is a risk that the ball studs could be more brittle than intended. If a ball stud is more brittle than expected, it could break, which could affect steering and increase the risk of a crash.

The recalled components were experimental parts manufactured using an unapproved heat treat process that the supplier inadvertently introduced into production. The remedy components will be produced to intended specification, according to the recall notice.

Meritor understands that the supplier is initiating an internal review to implement corrective actions and avoid reoccurrence when handling experimental materials and processes.

Dealers will replace the tie rod end and re-align the front axle, free of charge. When parts are available, remedy instructions and owner notifications will be distributed.

Owner notification letters are expected to be mailed September 9. Owners may contact Navistar customer service at 1-800-448-7825. Navistar's number for this recall is 24511.

The suspect vehicles were produced on these dates:

• HV: April 26-July 2

• HX: April 30-June 25

• LT: April 16-July 2

• MV: April 26-July 4

• RH: April 17-June 26

Paccar Adds to Kenworth, Peterbilt Recall

In June, Paccar recalled nearly 3,900 medium- and heavy-duty trucks with diesel powertrains for suspect USK ball studs, these installed on Dana components.

In a July 25 notice, the number of Paccar trucks in the recall grew to more than 7,400, as the recall was amended to expand the population to include chassis with Paccar and Meritor front axles that have suspect USK tie rod assemblies.

The Paccar recall affects 2025 model year:

• Kenworth K270, K370, L770, T280, T380, T480, T680, T880, W900, W990

• Peterbilt 220, 520, 536, 537, 548, 567, 579, and 589

The affected trucks were produced between April 10 and July 3.

In Paccar’s case, they advised that suspect vehicles not be driven until the remedy has been completed.

Owner notification letters in the Paccar recall are expected to be mailed August 11, 2024.