ULTIMAAX 60K • 70K Shown

FIGURE 8-37

Equalizing
Beam

Cotter Pin

17/8" Slotted Nut

Beam End Shaft
Beam End Adapter
17/8" Slotted Nut

17730-301

Beam End
Adapter

Chisel
Recess

Adapter
Flat Side
Vertical

Beam End Adapter
Adapter Style
End Bushing

Chisel Recess

49

Component Replacement

ULTIMAAX® for Kenworth Vehicles
5. Support the end of the equalizing beam as it may drop when the other adapter is removed.
6. Remove remaining adapters.
7. When the adapter has enough clearance between the axle bracket and the adapter flange,
use a bent chisel as shown in Figure 8-35 to wedge and force the adapter out.
THE ADAPTER REMOVAL PROCESS CAN CAUSE DAMAGE. REUSE OF DAMAGED OR WORN ADAPTERS
COULD RESULT IN A COMPONENT FAILURE LEADING TO ADVERSE VEHICLE HANDLING AND POSSIBLE
PERSONAL INJURY.

NOTE

Due to the process necessary to remove the adapters, the adapter can be subjected to damage.
DO NOT reuse worn or damaged adapters. Replace as necessary.
8. Remove the equalizing beam assembly from vehicle as detailed in the Equalizing Beam
Disassembly instructions in this section.
9. Position the equalizing beam in the shop press and align the End Bushing Removal /
Replacement Adapter with the tapered end facing the bushing to be removed, see Figure 8-38.
CHECK TO INSURE PROPER ALIGNMENT OF TOOLING ADAPTERS WITH EQUALIZING BEAM
COMPONENTS BEFORE APPLYING FULL HYDRAULIC PRESSURE WITH A SHOP PRESS.

10. Apply hydraulic force and push out the old bushing.
FIGURE 8-38

FIGURE 8-39

END BUSHING REMOVAL

END BUSHING INSTALLATION

End Bushing
Removal / Replacement
Adapter Tool
Part No. 66086-101

End Bushing
Removal / Replacement
Adapter Tool
Part No. 66086-101

End
Bushing

Clamp

End
Bushing
Equalizing Beam

Equalizing Beam

Receiver

FIGURE 8-40
Adapter Style
End Bushing

ASSEMBLY
1. Clean the end bushing bore with a cylinder
ball hone or emery paper. Clean any debris.
2. Lubricate the equalizing beam bore and
the equalizing beam center bushing outer
metal sleeve with an NLGI#2 – EP (Extreme
Pressure) grease, see Figure 8-40.
3. Position the end bushing removal / replacement adapter, with the tapered end facing
away from the new bushing, onto the clamp,
see Figure 8-39.

Equalizing Beam
End Hub

Outer Metal

Equalizing
Beam

NOTE
Lubricate the inside diameter of END HUB and
the end bushing OUTER METAL with NLGI#2-EP
(Extreme Pressure) lithium base grease

4. Wrench tighten the clamp onto the bushing and the adapter as shown in Figure 8-39.

Component Replacement

50

17730-301

ULTIMAAX® for Kenworth Vehicles
ENSURE PROPER ALIGNMENT OF TOOLING ADAPTERS WITH EQUALIZING BEAM COMPONENTS BEFORE
APPLYING FULL HYDRAULIC PRESSURE WITH A SHOP PRESS.

5. Apply hydraulic force and press the new bushing into place. The bushing will be completely
seated when the clamp makes contact with the beam face.
6. Install one adapter through the axle bracket leg at the wheel side, into the beam end bushing,
see Figure 8-41.
7. Install the other adapter through the axle bracket leg at the axle side, taking advantage of the
cut-off flange on the adapter to clear the axle.
FIGURE 8-41
Equalizing Beam

Cotter Pin

ULTIMAAX 60K • 70K Shown

17/8" Slotted Nut
17/8" Slotted Nut
Tightening Torque
125 ft. lbs. (170 Nm)
+ 90° rotation or
700 ± 50 ft. lbs. (949 ± 68 Nm)

Beam End Adapter
Beam End Shaft
Beam End Adapter

Adapter Style
End Bushing

FIGURE 8-42

8. Insert adapter connections, see Figure 8-42.
9. Rotate the adapters so the adapter cut off flats
are vertical as shown in Figure 8-42.
NOTE

Axles must be in operational position before fasteners are tightened to prevent pre-loading of the rubber
bushing.

Axle Bracket
Adapter
Equalizing
Beam

Adapter

10. Assemble one slotted nut to the shaft and install
Flat Side
the cotter pin. Place a suitable wrench on the
Vertical
Chisel Reliefs
nut and ensure the wrench is locked in place
(braced) to prevent movement. Tighten using one of the following torque procedure.

TORQUE PROCEDURE
IF THE RECOMMENDED TORQUE VALUE IS NOT PROPERLY MAINTAINED, THE METAL SURFACES OF THE
AXLE BRACKET LEGS, HOLES, ADAPTERS AND RUBBER BUSHING INNER METALS CAN EXPERIENCE
EXCESSIVE WEAR AND/OR FAILURE. THIS CAN CAUSE SEPARATION OF COMPONENTS AND ADVERSE
VEHICLE HANDLING, PROPERTY DAMAGE OR PERSONAL INJURY.

A simple torque wrench will not be sufficient to obtain the proper torque requirement. The proper
torque requirement can be obtained with the use of a torque multiplier. If one is not available the
use of a slug wrench is recommended.

METHOD A: TORQUE MULTIPLIER
You will need:
■■ Torque Multiplier

a. Assemble the opposite nut and use a torque wrench with multiplier.
b. Tighten the nut to torque multiplier value

700 ± 50 Foot Pounds torque, see Table 1.

DO NOT BACK OFF NUT TO INSTALL COTTER PIN, DOING SO MAY REDUCE THE TIGHTENING TORQUE
BELOW THE REQUIRED SPECIFICATION.

c. Install cotter pin. The nut may be advanced to the next nut slot. DO NOT back off nut.
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Component Replacement

ULTIMAAX® for Kenworth Vehicles
METHOD B: SLUG WRENCH
You will need:
■■ Two slug wrenches (see Figure 8-43), 4 pound hammer

a. Assemble the opposite nut and using a torque wrench, tighten the nut to the initial torque
value shown in Table 1.
FIGURE 8-43
TABLE 1

¾"

TORQUE SPECIFICATIONS

14¾"

SLUG WRENCH METHOD
1

/16" R

1

/8" R

5"

2"

125 Foot
Pounds

2½"
13

2 /16"

1
⁄4 or
90º turn
on
castle
nut

TORQUE
MULTIPLIER
700 ± 50
Foot Pounds

Min. Hex 12 Point

FIGURE 8-44

b. Remove torque wrench and
replace with the Slug Wrench.
Using a four pound hammer,
tighten the assembly by hitting the slug wrench near the
handle as shown in Figure 8-44
until the nut has been turned to
the degrees specified in Table 1.

Axle

DO NOT BACK OFF NUT TO INSTALL
COTTER PIN, DOING SO MAY REDUCE
THE TIGHTENING TORQUE BELOW THE
REQUIRED SPECIFICATION.

Slug Wrench

Axle Bracket Legs

Equalizing Beam
End Hub

4 lb. Hammer

Locked in Place
(Braced)

REPEATED HAMMERING BEYOND THE DEGREE SPECIFIED CAN CAUSE COMPONENT DAMAGE.

c. Install cotter pin. The nut may be advanced to the next nut slot, DO NOT back off nut.
INSUFFICIENT TIGHTENING TORQUES CAN CAUSE PREMATURE WEAR AND DAMAGE TO THE AXLE
BRACKET LEGS, HOLES AND/OR BEAM END CONNECTION COMPONENTS, THIS CAN FURTHER CAUSE
FAILURE AND SEPARATION OF COMPONENTS, AND RESULT IN ADVERSE VEHICLE HANDLING, SEVERE
PERSONAL INJURY OR DEATH. MAINTAIN PROPER TIGHTENING TORQUES AT ALL TIMES.

CROSS TUBE
A cross tube seldom requires replacement, usually only when it has been bent, possibly due to
hitting an object. A bent cross tube may cause misalignment of the axles, and must be replaced
immediately to eliminate abnormal tire wear.

METHOD A: EQUALIZING BEAM REMOVAL
Follow the steps in the Equalizing Beam Component Replacement procedure in this section.
Within the procedure, after removal of the equalizing beams when the equalizing beams are
separated, remove and replace cross tube.

Component Replacement

52

17730-301

ULTIMAAX® for Kenworth Vehicles
METHOD B: CENTER BUSHING END PLUG REMOVAL
You will need:
■■ Cross Tube Service Kit 60961-759 for 46K•52K•60K or 60961-875 for 70K, (see Parts Lists

Section of this publication)

■■ Cutting Torch
■■ Welding Equipment and Hole Saw (needed for 46K•52K•60K)

DISASSEMBLY
1. Use a work bay with a level surface.
2. Chock the front steer axle wheels.
FOLLOW THE SAFETY GUIDELINES FOR OPERATING THE TORCH. USE CAUTION AS PARTS MAY BE HOT.

3. Use a cutting torch to make two cuts in the cross tube, see Figure 8-45.
FIGURE 8-45
ULTIMAAX 52K Shown

Equalizing Beam

Center Bushing
NOTE
DO NOT grease the cross tube
or the center bushing

Use a torch to make two cuts
in the cross tube

4. Remove the cut section of the cross tube and slide the remaining sections out of the center
bushings and discard.
5. Remove only one center bushing end plug from the suspension:
■■

46K • 52K • 60K – Use a 2" (50.8 mm) hole saw, see Figure 8-46

■■

70K – Remove circlip, see Figure 8-47

ASSEMBLY
1. Clean the open end of the center bushing bore to approximately 1" (25.4 mm) depth of weld
and debris.
2. From the open center bushing slide the new cross tube into both center bushings.
3. It may be necessary to use a floor jack under one or both equalizing beams to align the cross
tube.
4. Once the new cross tube has been inserted,

17730-301

■■

46K • 52K • 60K – Position the end plug ¼" (6.6 mm) recessed in the center bushings
and tack weld, see Figure 8-46. Check end plug position, final weld shall be a ¼" (6.6
mm) fillet.

■■

70K – install new end plug and circlip, see Figure 8-47

53

Component Replacement

ULTIMAAX® for Kenworth Vehicles
FIGURE 8-46

FIGURE 8-47
46K • 52K • 60K

Center Bushing
Rubber

70K
Center Bushing
Rubber

Equalizing
Beam

OUTBOARD

Equalizing
Beam

INBOARD OUTBOARD

Welded
End Plug
Recessed ¼"

Center Bushing

Open end
of center
bushing

Welded
End Plug
Recessed ¼"

INBOARD
Center Bushing

Open end
of center
bushing

¼"
recessed
¼" final
fillet weld

TORQUE RODS
THE ULTIMAAX SUSPENSION INCORPORATES TORQUE RODS FOR VEHICLE STABILITY. IF THESE
COMPONENTS ARE DISCONNECTED OR ARE NON-FUNCTIONAL THE VEHICLE SHOULD NOT BE
OPERATED. FAILURE TO DO SO CAN RESULT IN ADVERSE VEHICLE HANDLING AND POSSIBLE TIRE
CONTACT WITH THE FRAME OR THE SUSPENSION.
■■

V-RODS

DISASSEMBLY
1. Chock the front wheels of the vehicle.
2. Remove and discard the V-rod mounting fasteners.
3. Remove the V-rod.
4. Inspect the mounting surface for any wear or damage. Repair or replace as necessary.

ASSEMBLY
1. Install the V-rod.
2. Install the new mounting fasteners that were removed.
NOTE

Hendrickson recommends the use of Grade 8 bolts and Grade C locknuts. If flange head bolts
and locknuts are not used then hardened structural washers must be used under bolt heads and
locknuts.
3. Prior to tightening, ensure that the vehicle is at the proper ride height. Tighten all fasteners to
the required torque specification. Refer to vehicle manufacturer for specifications.
4. Remove wheel chocks.
■■

LONGITUDINAL TORQUE RODS

DISASSEMBLY
1. Chock the front wheels of the vehicle.
SERVICE HINT

To remove all the load from the longitudinal torque rod, raise or lower the pinion as needed. This
will ease the removal of the longitudinal torque rod.
2. Support the pinion on the axle being serviced.

NOTE

Component Replacement

Prior to disassembly of the longitudinal torque rod, note the quantity and orientation of the longitudinal torque rod shims. It is required that the longitudinal torque rod shims are installed in the
same orientation and location as removed to preserve the existing alignment.
54

17730-301

ULTIMAAX® for Kenworth Vehicles
3. Remove the torque rod mounting fasteners and shims (if equipped).
4. Remove the fasteners that connect the longitudinal torque rod to the cross member and axle
brackets.
5. Remove longitudinal torque rod.

ASSEMBLY
1. Install longitudinal torque rod.
2. Install the fasteners and any shims that were removed to the cross member and axle brackets.
NOTE

Hendrickson recommends the use of Grade 8 bolts and Grade C locknuts. If flange head bolts
and locknuts are not used then hardened structural washers must be used under bolt heads and
locknuts.
3. Tighten all fasteners to vehicle manufacturer’s torque specifications.
4. Verify proper pinion angle, and correct with drop in shims between the torque rod bar pin and
the cross member or axle bracket depending on the direction of adjustment needed. Contact
the vehicle manufacturer for proper pinion angle specifications.
5. Remove wheel chocks.
■■

TRANSVERSE TORQUE RODS

DISASSEMBLY
1. Chock the front wheels of the vehicle.
SERVICE HINT

Note the quantity and location of shims removed to maintain the lateral alignment of the axle
during assembly. See Alignment & Adjustments Section of this publication.
2. Remove the torque rod mounting fasteners.
3. Remove the transverse torque rod.
4. Inspect the mounting surfaces for any wear or damage. Repair or replace as necessary.

ASSEMBLY
1. Install the transverse torque rod.
2. Install the mounting fasteners and any shims that were removed.
NOTE

Hendrickson recommends the using Grade 8 bolts and Grade C locknuts for all torque rod
attachments.
3. Prior to tightening, ensure that the vehicle is at the proper ride height. Tighten all fasteners to
the required torque specification. Refer to original equipment manufacturer for specifications.
4. Check the lateral alignment. If not within vehicle manufacturer’s specified range, a lateral
alignment is necessary. See Lateral Alignment in the Alignment & Adjustments Section of this
publication.
5. Remove the wheel chocks.

17730-301

55

Component Replacement

ULTIMAAX® for Kenworth Vehicles
XTRB TORQUE ROD BUSHINGS

FIGURE 8-48

You Will Need:
■■ A vertical press with a capacity of at least 10 tons
■■ Shop made receiving tool and installation / removal

tool, refer to the Special Tools Section of this publication for more information.

BUSHING REMOVAL
1. Remove torque rods as detailed in Torque Rod
Disassembly instructions in this section.
DO NOT USE HEAT OR USE A CUTTING TORCH TO REMOVE
THE BUSHINGS FROM THE TORQUE ROD. THE USE OF HEAT WILL ADVERSELY AFFECT THE STRENGTH
OF THE TORQUE ROD, HEAT CAN CHANGE THE MATERIAL PROPERTIES. A COMPONENT DAMAGED IN
THIS MANNER CAN RESULT IN THE ADVERSE VEHICLE HANDLING AND POSSIBLE PERSONAL INJURY OR
PROPERTY DAMAGE.

2. Straddle Mount Bar Pin Bushing (see Figure 8-48) —When servicing a straddle mount bar
pin bushing assembly, mark the clocking position of the straddle mount bar pin flats with a
paint stick on the torque rod end hub prior to disassembly, see Figure 8-49. This marking will
serve as a guide when installing the new bushing so the original clocking position can be
retained.
3. Taper Pin Bushing (see Figure 8-48) — Remove the fastener and the concave washer from
the taper pin bushing.
4. Support the torque rod end hub and centered on the receiving tool (for a tapered bushing,
have the tapered stud pointing down). Ensure the torque rod is squarely supported on the
press bed for safe­ty.
5. Install the removal tool, see Figure 8-50.