Solution K12193443
Monday, March 23, 2020 1:16:40 PM CET

** SOLUTION **
Title

Mack Chassis - Rear Drive Transverse Torque Rod Bracket Failure; Torque Rod Bracket
Broken/Studs Broken On Rear Carrier

Mack Models
LEU , LR , MRU - TerraPro , TE - TerraPro , AN - Anthem , CHU - Pinnacle, Axle

Mack Model

back , CXU - Pinnacle, Axle front , GR - Granite , GU - Granite , PI - Pinnacle , TD Titan

** SOLUTION **
Cause
Vehicles meeting the criteria for this solution may experience failure of the rear drive
transverse torque rod bracket. An example is shown below:

This issue was found to have begun following the introduction of a newer lightweight
bracket for the torque rod. Failure occurs after the studs loosen on the rear of the carrier,
or when the bracket does not sit flat on the carrier. This pushes the load in to the torque
rod bracket.
At this time the issue is still under investigation. This solution will be updated when
more information is available.

Soluti

If a vehicle has experienced a failure as described in the section above:

on

Inspection
1. Check the part number of the bracket currently installed.

• The affected bracket part number is 22539545. It is also possible that this issue can be encountered
with part 21593018.
• NOTE: Multiple previous part numbers supersede to the numbers above. The part number should be
obtained from the bracket itself.
2. Check to see if the torque rod bracket is seated flush against the carrier housing.

Repair
If the bracket is found to not be flush with the carrier housing follow the steps below:
1. Inspect for a raised boss area on the carrier. An affected area is circled in the picture below:

2. Remove the studs from the housing.
3. Grind the raised area smooth to match the flat surface for the bracket. Be careful to grind the area smooth
so no cracks form.
4. Clean and re-install the studs with Loctite 263. Torque to 225-275 lb-ft (305-373 Nm).

Bracket 22539545

Solution visibility

Dealer distribution

Function(s)/component(s) affected
Function affected

suspension mounting bracket

Function Group
Function Group

46 front axle; rear axle; drive shaft

Administration
Author

UT7584V

Dealer ID

UT7584V

Last modified by

RU4469V

Creation date

11-02-2020 17:02

Date of last update

17-03-2020 21:03

Status

Published

UNCONTROLLED COPY. Printed document is for temporary use only and should not be retained.