MACK U 1972: STEERING:LINKAGES:KNUCKLE:SPINDLE:ARM

General Information

NHTSA Campaign ID Number: 78V171000

Make Model Year
MACK U 1972
Date Owners Notified Date Received by ODI Date Added to Database
1979-08-10 1978-08-08 1979-10-12

Manufacturers Involved: Mack Trucks, Inc.

Component: STEERING:LINKAGES:KNUCKLE:SPINDLE:ARM

Potential Number Of Units Affected: 2100

Report Initiator: MFR MFR Report

Summary

DEFICIENCIES, IN THE FORM OF FORGING LAPS, CRACKS AND EXCESSIVE DECARBURIZATION DURING HEAT TREATMENT, EXIST IN THE STEERING KNUCKLES. STRESSES IMPOSED WITH INTEGRAL HYDRAULIC POWER STEERING MAY LEAD TO A FAILURE IN THE AREA OF THE STEERING ARM ATTACHING BOSS. THIS TYPE OF FAILURE WOULD CAUSE LOSS OF STEERING CONTROL.

Remedy

DEALER WILL INSPECT AND, IF NECESSARY, REPLACE THE LEFT STEERING KNUCKLE WITH AN IMPROVED TYPE OF KNUCKLE.

Notes

VEHICLE DESCRIPTION: TRUCK TRACTORS.SYSTEM: STEERING; STEERING KNUCKLE.CONSEQUENCES OF DEFECT: LOSS OF STEERING CONTROL COULD CAUSE A VEHICLEACCIDENT.