6. Press directly on the removal tool until the bushing clears the torque rod end hub, see
Figure 8-51.
FIGURE 8-49

FIGURE 8-50

FIGURE 8-51

Mark the clocking position of the
bar pin flats with a paint stick
on the torque rod end hub
Torque Rod
Bushing
Installation /
Removal Tool

Torque Rod
Bushing
Receiving Tool

Component Replacement

56

17730-301

ULTIMAAX® for Kenworth Vehicles
BUSHING INSTALLATION
1. Clean and inspect the inner diameter of the torque rod end hubs, see Figure 8-52.
SERVICE HINT

DO NOT use a paraffinic oil, or soap base lubricant. Such lubricants can cause adverse reactions
with the bushing, causing premature failure.
2. Lubricate the inner diameter of the torque rod end hubs and the outer metal of new bushings
with NLGI #2 EP grease, see Figure 8-53.
FIGURE 8-52

FIGURE 8-53

Inspect and clean the inner
diameter of torque rod
end hubs

Apply NLGI #2-EP (Extreme Pressure)
lubricant to the inner diameter of torque
rod end hub and bushings

3. Support the torque rod end hub centered on the receiving tool. Ensure the torque rod is
squarely supported on the press bed for safety.
4. Straddle Mount — Place the straddle mount bushing in the end hub and re-align the bar pin
bushings to the mark made prior to removal as shown in Figure 8-49.
5. Taper Pin — Place the taper pin bushing in the end
hub with the taper pointing down. Tighten 5⁄8" bolt
head to 65 ± 5 (88 ± 7) torque, see Figure 8-54.

FIGURE 8-54
5
/8" Bolt Head
Tightening Torque
65 ± 5 ft. lbs. (88 ± 7 Nm)

6. Using the shop made tool, place the installation tool
on the bushing and press in, see Figure 8-51.
7. Ensure the bushing is centered within the hub of the
torque rod.
8. Wipe off the excess lubricant.
9. Replace torque rod assembly as detailed in the
Transverse or Longitudinal Torque Rod Component
Replacement Section in this publication.

17730-301

57

Taper Pin
Bushing

Component Replacement

ULTIMAAX® for Kenworth Vehicles
SECTION 9

Torque Specifications

HENDRICKSON RECOMMENDED TORQUE VALUES PROVIDED
IN FOOT POUNDS AND IN NEWTON METERS

5a.
200 ± 25 ft. lbs
(271 ± 34 Nm)

46K • 52K Capacity

3.
325 ft. lbs (440 Nm)
+ 90° Rotation
OR
560 ± 30 ft. lbs
(760 ± 40 Nm)

5b.
65 ± 5 ft. lbs
(88 ± 7 Nm)

1.
200 ± 20 ft. lbs
(270 ± 30 Nm)

2.
30 ± 2 ft. lbs
(41 ± 3 Nm)

7.
170 ± 20 ft. lbs
(231 ± 27 Nm)

6.
80 ± 10 ft. lbs
(109 ± 19 Nm)

4a.
525 ± 75 ft. lbs
(712 ± 102 Nm)

Torque Specifications

58

4b.
575 ± 75 ft. lbs
(780 ± 102 Nm)

17730-301

ULTIMAAX® for Kenworth Vehicles

ULTIMAAX 46K • 52K for Kenworth Vehicles
HENDRICKSON RECOMMENDED TORQUE SPECIFICATIONS
FASTENER
NO.

COMPONENT

TORQUE VALUE

*QUANTITY

SIZE

FOOT
POUNDS

NM

1

Saddle Assembly to Center Bushing Locknut

8

M16

200 ± 20

270 ± 30

2

Saddle Assembly to Progressive Load Spring Flange Locknut

8

M10

30 ± 2

41 ± 3

3

Saddle Assembly Halves Flange Locknuts

8

M20

325 + 90°
rotation or
560 ± 30

440 + 90°
rotation or
760 ± 40

at the Locknut

8

1"-8 UNC

525 ± 75

712 ± 102

at the Bolt Head

8

1"-8 UNC

575 ± 75

780 ± 102

at the Locknut

2

1½"-12 UNF

200 ± 25

271 ± 34

at the Bolt Head

2

⁄8"-11 UNC

65 ± 5

88 ± 7

4a
4b
5a
5b

Bar Pin End Bushing
Transverse Torque Rod to Axle

5

NOTE: * Quantities shown are per suspension.
** Torque values shown in this publication apply only if Hendrickson supplied fasteners are used. If non Hendrickson fasteners
are used, follow the torque specification listed in the vehicle manufacturer’s service manual.

17730-301

59

Torque Specifications

ULTIMAAX® for Kenworth Vehicles
HENDRICKSON RECOMMENDED TORQUE VALUES PROVIDED
IN FOOT POUNDS AND IN NEWTON METERS

60K • 70K Capacity
6.
420 ± 20 ft. lbs
(569 ± 27 Nm)
3.
325 ft. lbs (440 Nm)
+ 90° Rotation
OR
560 ± 30 ft. lbs
(760 ± 40 Nm)

5.
420 ± 20 ft. lbs
(569 ± 27 Nm)

1.
558 ± 32 ft. lbs
(757 ± 43 Nm)

2.
30 ± 2 ft. lbs
(41 ± 3 Nm)

4.
125 ft. lbs. (170 Nm)
+ 90° Rotation OR
700 ± 50 ft. lbs
(949 ± 68 Nm)

Torque Specifications

60

17730-301

ULTIMAAX® for Kenworth Vehicles

ULTIMAAX 60K • 70K for Kenworth Vehicles
HENDRICKSON RECOMMENDED TORQUE SPECIFICATIONS
FASTENER
NO.

COMPONENT

TORQUE VALUE

*QUANTITY

SIZE

FOOT
POUNDS

NM

1

Saddle Assembly to Center Bushing Locknut

8

M20

558 ± 32

757 ± 43

2

Saddle Assembly to Progressive Load Spring Flange
Locknut

8

M10

30 ± 2

41 ± 3

M20

325
+ 90°
rotation or
560 ± 30

440
+ 90° rotation
or 760 ± 40
170
+ 90° rotation
or 949 ± 68

3

Saddle Assembly Halves Flange Locknuts

8

4

Adapter Style End Bushing

8

17⁄8"

125
+ 90°
rotation or
700 ± 50

5

V-rod to Corner Bracket

8

M20

420 ± 20

569 ± 27

6

V-rod to Axle Apex Bracket

2

M20

420 ± 20

569 ± 27

NOTE: * Quantities shown are per suspension.
** Torque values shown in this publication apply only if Hendrickson supplied fasteners are used. If non Hendrickson fasteners
are used, follow the torque specification listed in the vehicle manufacturer’s service manual.

17730-301

61

Torque Specifications

ULTIMAAX® for Kenworth Vehicles
SECTION 10

Troubleshooting Guide
ULTIMAAX for Kenworth Vehicles
TROUBLESHOOTING GUIDE
CONDITION
Suspension
has harsh or
bumpy ride

Vehicle leans

Irregular tire
wear

Loose or
missing
suspension
fasteners

POSSIBLE CAUSE
Damaged shock absorber

Replace shock absorbers

Damaged progressive load spring

Replace progressive load springs, must be replaced in pairs

Damaged shear spring

Replace shear spring

Vehicle overloaded

Redistribute or reduce load to correct weight

Damaged progressive load spring

Replace progressive load springs, must be replaced in pairs

Damaged shear spring

Replace shear spring

Bent cross tube

Replace cross tube

Weight bias

Redistribute load to correct weight bias

Incorrect axle alignment

Axle alignment is permanently set at the time of vehicle manufacture.
Contact vehicle manufacturer.

Bent cross tube

Replace cross tube

Damaged, bent, cracked suspension
component

Replace damaged component

Suspension is overloaded
Improper torque or over torque
Suspension is overloaded

Frame hanger
cracked

Saddle leg
to equalizing
beam contact

CORRECTION

Reduce and/or redistribute load to correct weight
Replace and/or properly tighten fasteners to the proper torque specification
Increase inspection interval of fasteners
Replace and/or properly tighten fasteners to the proper torque specification
Replace frame hanger assembly
Reduce and/or redistribute load to correct weight
Replace frame hanger assembly

Loose or missing suspension fasteners

Increase inspection interval of fasteners
Replace fasteners and/or properly tighten fasteners to the proper torque
specification

Damaged frame hanger assembly

Replace frame hanger assembly

Damaged, bent, worn, or cracked
suspension component(s)

Replace damaged component

Cross tube bent or missing

Replace cross tube

Loose or worn saddle hex bolts

Replace saddle hex bolts, inspect mating components

Saddles not center on equalizing beam

Center saddles on the equalizing beam

Saddles not center on center bushing

Replace center bushing

Troubleshooting Guide

62

17730-301

ULTIMAAX® for Kenworth Vehicles

17730-301

63

Troubleshooting Guide

www.hendrickson-intl.com

Truck Commercial Vehicle Systems
800 South Frontage Road
Woodridge, IL 60517-4904 USA

17730-301 Rev C 08-18

1.866.755.5968 (Toll-free U.S. and Canada)
1.630.910.2800 (Outside U.S. and Canada)
Fax 1.630.910.2899

Information contained in this literature was accurate at the time of publication. Product changes may have been made after the copyright date that are not reflected.
© 2016 – 2018 Hendrickson USA, L.L.C. All Rights Reserved

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