Trucks

Mack Trucks, Inc.
Greensboro, NC USA

SB-10043808-1362

Date

Group

No.

Release

Page

2.2012

652

004

1

1( 5 )

Torque Rod Replacement
CHU, CXU, GU, TD

FSB 652-004, Torque Rod Replacement
(February 2012)
Note: This bulletin does not apply to Mack Trucks Australia.
Note: Information is subject to change without notice.
Illustrations are used for reference only, and may differ slightly from the actual vehicle
being serviced. However, key components addressed in this information are represented
as accurately as possible.
Torque rod on front rear axle makes contact with carrier during articulation. The following
procedure must be performed on the front and rear torque rod at the same time.
This applies to MACK axles only.

PV729-FSB652-004

USA48492

Mack Trucks, Inc.

Date
2.2012

Group

No.

Release

652

004

1

Torque Rod Replacement (Front and Rear Lateral Torque Rods)
1 Park the vehicle on a level surface with the transmission in neutral and wheels chocked.
2
Note: Kit does not include torque rods, which may be required.
Parts List: Kit 85130549
Quantity

Part ID
Number

Part
Number

Description

Note for Relocation of
Torque Rod

4

1

966360

Screw M14x50

Additional Standard Part

8

2

966838

Washer

Additional Standard Part

4

3

21679186

Plate Reinforcement

New Part to be Used

8

4

971097

Nut M14

Additional Standard Part

4

5

975128

Screw M16

Additional Standard Part

2

6

21679179

Bracket Torque Rod

New Part to be Used

4

7

20706261

Washer

Additional Standard Part

4

8

969318

Nut M16

Additional Standard Part

4

9

25109220

Screw

Part to be Reused

4

10

25173404

Washer

Additional Standard Part

1

11

25176599

Torque Rod Front

May be required

1

12

25155774

Torque Rod Rear

May be required

4

13

25085424

Nut

New Standard Part to
be Used

4

14

966363

Screw M14x65

New Standard Part to
be Used

NA

15

Varies

Bump Stop

Part to be Reused

Support the wheel end with a jack stand supporting the rear axle and remove the rear
wheels and tires.
3 Disconnect the torque rod and all associated parts from the frame rail.

Page
2( 5 )

Mack Trucks, Inc.

Date
2.2012

Group

No.

Release

652

004

1

4

W6070237

Note: Numbered call-outs correspond to “Part ID Number” in the “Parts List”.
Assemble the new parts (inner and outer plates) onto the frame rail where the torque rod
will be re-installed. Tighten the fasteners to 200 ± 30 Nm (148 ± 22 ft-lb).
5

W6070238

Note: Prior to drilling new holes in frame ensure that all six existing holes in frame line
up with holes in new reinforcement plates. Then, use reinforcement plate holes "D" as
guide to drill holes "C" in frame as directed below. Failure to do so will result in frame rail
damage requiring frame rail replacement.
Drill two new 17 mm (0.67 in.) holes in the frame rail using the holes in the plate installed
in the previous step as a guide.

Page
3( 5 )

Mack Trucks, Inc.

Date
2.2012

Group

No.

Release

652

004

1

6

W6070239

Note: Numbered call-outs correspond to “Part ID Number” in the “Parts List”.
Install the new torque rod bracket and fasteners. Tighten the fasteners to 610–813 Nm
(450 – 600 ft-lb).
7

W6070240

Note: Numbered call-outs correspond to “Part ID Number” in the “Parts List”.
Connect the torque rod to the new holes on the frame rail torque rod bracket and tighten
to specification 610–813 Nm (450 – 600 ft-lb).
8 Repeat steps 1 - 7 for rear torque rod.

Page
4( 5 )

Mack Trucks, Inc.

Date
2.2012

Group

No.

Release

652

004

1

9 Install the wheels and tires and tighten the wheel nuts to specification.
10

W6066446

Check the thrust and lateral alignment of the drive axles.

•
•

Truck should initially be reassembled using existing torque rods.

•

If 5 mm specification is achieved by 'Y’ and X‘ measurements having a difference of
less than 5 mm, no further work is required. DO NOT REPLACE TORQUE RODS.

•

If 5 mm specification cannot be achieved by 'Y’ and X‘ measurements having a
difference of less than 5 mm, then replacement of torque rods using part numbers
listed on first page is required and may or may not require shims. If torque rods are
replaced then lateral alignment should be rechecked.

Perform measurements of tandem alignment per illustration. The difference between
measurements 'Y’ and 'X' should be less than 5 mm (0.2 in.).

Reimbursement
This repair may be eligible for reimbursement if a product failure was experienced
within time and mileage limits of the applicable Warranty coverage. Reimbursement
is obtained via the normal claim handling process.
Claim Type (used only when uploading from the Dealer Bus.
Sys.)

01

Labor Code
Primary Labor Code (Both sides without torque rods)

1353B-01-80 —
1.7 hrs

Causal Part

25155635

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