United States 78V170000
Mack Trucks, Inc.
The problem
THE POSSIBILITY EXISTS THAT THE ALUMINUM ENGINE REAR SUPPORT BRACKETS MAY FAIL DUE TO METAL FATIGUE. THIS TYPE OF FAILURE WOULD ALLOW THE ENGINE AND TRANSMISSION ASSEMBLY TO DISLOCATE DOWNWARD. THIS WILL RESULT IN THROTTLE CONTROL LOSS WITH THE ENGINE OPERATING CONTINUOUSLY IN THE MID TO UPPER RANGE OF THE GOVERNED SPEED RANGE.
What owners should do
DEALER WILL INSPECT AND, IF NECESSARY, REPLACE ALUMINUM SUPPORT BRACKETS WITH BRACKETS MADE FROM DUCTILE IRON FOR INCREASED STRENGTH.
Units 850