United States 93V024000
Mack Trucks, Inc.
The problem
THE CARRIER YOKE BOLTS WERE MANUFACTURED WITH WORN ROLLING THREAD DIES, CAUSING STRESS CONCENTRATIONS WHICH CAUSED CRACKS DURING THE QUENCHING PROCESS.
Risk
THIS CONDITION CAN CAUSE BOLT FAILURE AND ALLOW THEDRIVELINE TO SEPARATE FROM THE CARRIER ASSEMBLY.
What owners should do
REPLACE THE CARRIER YOKE BOLTS.
Units 4924