13. Remove the saddle halves and / or shear springs for replacement.

FIGURE 8-6

ULTIMAAX 63K Shown
M10 Flange Bolt
Frame Hanger

Progressive Rate
Spring

Saddle Assembly Half
(Inboard)

Spacer (if equipped)
Saddle Assembly Half
(Outboard)
M20 Flange Bolt

Shear Spring

Saddle Disassembly Tool
Part Number 66086-113L

M10 Flange Locknut
Tightening Torque
30 ± 2 ft. lbs
(41 ± 3 Nm)

M20 Flange Locknut
Tightening Torque
325 ft. lbs (440 Nm)
PLUS a 90° rotation,
OR 560 ± 30 ft. lbs
(760± 40 Nm)

NOTE: During assembly, it
may be necessary to use tape
to hold the shear spring in
position. After installation is
complete remove tape.

EACH FRAME HANGER ASSEMBLY WEIGHS APPROXIMATELY 104 TO 140 POUNDS (47 TO 63
KILOGRAMS), USE APPROPRIATE LIFTING DEVICES TO REMOVE OR INSTALL THE FRAME HANGER
ASSEMBLY. FAILURE TO DO SO CAN RESULT IN DAMAGE TO THE VEHICLE OR PERSONAL INJURY.

14. If replacing the frame hanger, remove the frame fasteners per the vehicle manufacturer’s
instructions. Remove frame hanger.

ASSEMBLY
1. If installing a new frame hanger continue to Step 2. If installing or servicing shear springs or
saddle assembly , proceed to Step 3.
EACH FRAME HANGER ASSEMBLY WEIGHS APPROXIMATELY 104 TO 140 POUNDS (47 TO 63
KILOGRAMS), USE APPROPRIATE LIFTING DEVICES TO REMOVE OR INSTALL THE FRAME HANGER
ASSEMBLY. FAILURE TO DO SO CAN RESULT IN DAMAGE TO THE VEHICLE OR PERSONAL INJURY.

2. Position the frame hanger assembly against the frame rail. Install fasteners per the vehicle
manufacturer’s instructions.
SERVICE HINT

During assembly, it may be necessary to use tape to hold the shear springs in position. After installation is complete remove tape.
3. Position the shear springs with the flanged flat side against the frame hanger with the shear
spring angled downward, see Figure 8-7.

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FIGURE 8-7

ULTIMAAX 63K Shown
TOP VIEW

SHEAR SPRING
Flange Flat Side
Notch
on Top

SIDE VIEW

Notch
on Top
Frame Hanger

Frame
Hanger
Shear Springs
Angled downward

Position shear springs
anged at side against
the frame hanger

Angled
Side

4. Apply NLGI #2–EP (Extreme Pressure) chassis lubricant to the threaded rod of the
Saddle Assembly Tool No. 66086‑108L, see
Figure 8-8.
NOTE

The threaded rod spacer and spacer nut are
designed and orientated to fit into the saddle
assembly openings, see Figure 8-10.
5. Apply P-80 lubricant to the shear spring’s
angled face and to the mating face of the
saddle halves, see Figure 8-9.
FIGURE 8-9

Shear Springs
Flanged Flat Side

FIGURE 8-8
Saddle Assembly Tool
Hendrickson Part No. 66086-108L

Apply NLGI #2–EP
Chassis Lubricant
Threaded Rod
Threaded Rod
Threaded Rod
Spacer

Threaded Rod
Spacer Nut

ULTIMAAX 63K Shown
Saddle Assembly Half
(Inboard)

Shear Spring
Angled Face Area

Mating faces of
Saddle Assembly

Saddle Assembly Half
(Outboard)

Lubrication
Apply P-80 lubricant to the angled
face area of the Shear Springs and
mating faces of the Saddle Assembly

6. On each side of one saddle assembly, rotate the threaded rod spacers and spacer nuts of the
saddle assembly tool until each are oriented properly into the saddle assembly openings, see
Figure 8-10.
SERVICE HINT

Use a mechanism to attach to the frame to aid in holding the saddle up while performing procedure (such as a strap or rope) attached to each saddle half and the frame or the vehicle body
to secure the saddle halves during installation or have an additional person assist to align the
saddle halves properly.
7. Position the inner saddle half into the frame hanger along with the shear springs, outer saddle
half and the saddle assembly tool, see Figure 8-11.
8. Bring both saddle halves together with the saddle assembly tool. Evenly tightening the saddle
assembly tool until both saddle halves are seated against each other.

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FIGURE 8-10

Saddle Assembly
Opening

Threaded Rod
Spacer

Saddle Assembly Tool
Hendrickson Part No. 66086-108L
FIGURE 8-11

9. Install the new M20 flange saddle fasteners. Tighten in the proper sequence shown in Figure
8-12 to 325 foot pounds plus a 90° rotation, or 560 ± 30 foot pounds torque.
10. Remove temporary tape from the shear springs if used during assembly.
11. Remove each of the saddle assembly tools.
12. Install the progressive load springs (PLS).
13. Install the progressive load spring M10 flange fasteners.Tighten to

30 ± 2 foot pounds torque.

14. Remove the frame supports.
15. Lower the frame of the vehicle while engaging the saddles on the equalizing beam’s center
bushings, see Figure 8-13.

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FIGURE 8-12

FIGURE 8-13

A SADDLE ASSEMBLY IS ATTACHED TO THE CENTER BUSHING OF EACH EQUALIZING BEAM WITH TWO
(2) SADDLE CAPS. EACH SADDLE CAP USES TWO (2) BOLTS TO CLAMP THE CENTER BUSHING INNER
METAL TO THE SADDLE. EACH SADDLE CAP MUST BE INSTALLED SO THAT THERE IS AN EVEN GAP
BETWEEN THE SADDLE CAP AND THE BASE OF THE SADDLE LEGS AS SHOWN IN FIGURE 8-14. IF EACH
SADDLE CAP IS NOT INSTALLED EVENLY, THE SADDLE LEGS COULD BECOME DEFORMED, RESULTING
IN BENT BOLTS OR DAMAGED SADDLES.

NOTE

Tightening the saddle cap fasteners properly will help prevent wear of mating components, such
as the beam center bushing, saddle, and saddle cap.
16. While tightening the saddle cap fasteners maintain an even gap between the saddle and
saddle cap, see Figure 8-14.
FIGURE 8-14

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FIGURE 8-15

17. Install the saddle cap fasteners and tighten evenly in several steps to
200 ± 20 foot pounds torque in proper sequence to achieve uniform
bolt tension, see Figure 8-15.
18. Install the tires.
19. Remove supports from the axles and lower the vehicle onto the ground.
20. Remove the wheel chocks.

PROGRESSIVE LOAD SPRING (PLS)
NOTE

The Hendrickson ULTIMAAX suspension progressive load springs must be replaced in pairs (left
side pairs or right side pairs or rear position pairs or front position pairs), even if only one PLS
shows unacceptable conditions. Replacement of only one PLS can cause uneven wear, and
higher premature wear for the one replaced.

DISASSEMBLY
1. Chock the front wheels of the vehicle.
2. Raise the vehicle’s frame until the saddle assembly contacts the bottom of the frame hanger
assembly. Support the vehicle’s frame at this height with safety stands.
3. Remove and discard the four M10 flange bolts that attach the progressive load springs to the
saddle assembly, see Figure 8-16.
4. Remove the PLS from the frame hanger assembly.
FIGURE 8-16

ASSEMBLY
1. Install the PLS into the
frame hanger assembly.
2. Install the four M10 flange
bolts that attach the PLS
to the saddle assembly.
The flange bolts must be
installed with the locknuts facing downward as
shown in Figure 8-16.
3. Tighten the PLS fasteners
to 30 ± 2 foot pounds
torque.
4. Remove the frame safety stands and lower the vehicle.
5. Remove the wheel chocks.

EQUALIZING BEAM
DISASSEMBLY
1. Chock the wheels of the steer axle.
2. Raise and support the drive axles with safety stands.
3. Remove the tires.
4. Support the pinion angle of the drive axles to prevent axle movement during service.
5. Remove the saddle cap bolts from both inboard and outboard sides of the equalizing beam.
6. Remove the saddle caps, see Figure 8-17.
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FIGURE 8-17

7. Raise the vehicle’s frame just enough to create a ½" (13 mm) gap between the saddles and
the center bushings. Support the vehicle’s frame at this height with safety stands.
THE WEIGHT OF THE EQUALIZING BEAM ASSEMBLY IS APPROXIMATELY 285 POUNDS (130
KILOGRAMS). PRIOR TO REMOVING THE END BUSHING BOLTS FROM THE EQUALIZING BEAM, SUPPORT
THE END OF THE EQUALIZING BEAM TO PREVENT IT FROM DROPPING. CARE SHOULD BE TAKEN AT
REMOVAL AND INSTALLATION TO PREVENT PERSONAL INJURY OR DAMAGE TO COMPONENTS.

8. Support both equalizing beams under the center bushing with floor jacks.
9. Adapter Style End Bushing – Proceed to Step 11.
NOTE

Prior to disassembly of the equalizing beam bar pin fasteners, note the orientation of the bar
pin alignment shims. It is required that the bar pin alignment shims are installed in the same
orientation and location as removed to preserve the existing vehicle alignment. Improper vehicle
alignment can increase tire wear.
10. Bar Pin Style End Bushing – Note the orientation and location of the bar pin shims.
11. Remove and discard end bushing fasteners.

SERVICE HINT

The center bushing will allow the cross tube and the equalizing beam to angle downward once
the equalizing beam end fasteners are removed.
12. Slowly lower the floor jacks and remove the equalizing beams from the axle brackets.
PRIOR TO REMOVING BOTH EQUALIZING BEAMS, SUPPORT THE PINION OF EACH DRIVE AXLE. FAILURE
TO DO SO CAN RESULT IN PERSONAL INJURY OR ALLOW THE AXLES TO SHIFT MAKING REASSEMBLY
MORE DIFFICULT.

13. Slide the equalizing beams off the cross tube and out from under the vehicle.
14. Remove the floor jacks from under the equalizing beams.

ASSEMBLY
1. Position the equalizing beams under the axles with floor jacks.

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SERVICE HINT

Ensure the equalizing beam’s center bushing end plug is located on the outboard side of the
equalizing beam, see Figure 8‑17.
2. Push down and install the cross tube into the center bushings of both equalizing beams.

SERVICE HINT

Increasing or decreasing the pinion angle may help align the axle bracket and the equalizing
beam end bushings.
THE WEIGHT OF THE EQUALIZING BEAM ASSEMBLY IS APPROXIMATELY 285 POUNDS (130
KILOGRAMS). PRIOR TO REMOVING THE END BUSHING BOLTS FROM THE EQUALIZING BEAM, SUPPORT
THE END OF THE EQUALIZING BEAM TO PREVENT IT FROM DROPPING. CARE SHOULD BE TAKEN AT
REMOVAL AND INSTALLATION TO PREVENT PERSONAL INJURY OR DAMAGE TO COMPONENTS.

3. Using the floor jacks, slowly raise both equalizing beams and cross tube as an assembly into
the axle brackets. Ensure each equalizing beam end bushing correctly engages its respective
axle bracket.
4. Adapter Style End Bushing – Proceed to Step 6.
5. Bar Pin Style End Bushing – Install bar pin shims in the same orientation and location as
noted prior to disassembly.
6. Install new end bushing fasteners into both beams. Tighten the end bushing fasteners to:
■■ Adapter

Style End Bushing – 125 foot pounds + 90° rotation or 700 ± 50 foot pounds
torque.
■■ Bar Pin Style End Bushing at the –
●● Locknuts
525 ± 75 foot pounds (712 ± 102 Nm) or
●● Bolthead
575 ± 75 foot pounds (780 ± 102 Nm) torque

7. Remove the frame supports.
8. Lower the frame of the vehicle while engaging and centering the saddles on the equalizing
beam’s center bushings, see Figure 8-18.
FIGURE 8-18

A SADDLE ASSEMBLY IS ATTACHED TO THE CENTER BUSHING OF EACH EQUALIZING BEAM WITH TWO
(2) SADDLE CAPS. EACH SADDLE CAP USES TWO (2) BOLTS TO CLAMP THE CENTER BUSHING INNER
METAL TO THE SADDLE. EACH SADDLE CAP MUST BE INSTALLED SO THAT THERE IS AN EVEN GAP
BETWEEN THE SADDLE CAP AND THE BASE OF THE SADDLE LEGS AS SHOWN IN FIGURE 8-19. IF EACH
SADDLE CAP IS NOT INSTALLED EVENLY, THE SADDLE LEGS COULD BECOME DEFORMED, RESULTING
IN BENT BOLTS OR DAMAGED SADDLES.

NOTE

Tightening the saddle cap fasteners properly will help prevent wear of mating components, such
as the beam center bushing, saddle, and saddle cap.
9. While tightening the saddle cap fasteners maintain an even gap between the saddle and
saddle cap, see Figure 8-19.
10. Tighten the saddle cap fasteners evenly in several steps to 200 ± 20 foot pounds torque in
proper sequence to achieve uniform bolt tension, see Figure 8-20.

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FIGURE 8-19

FIGURE 8-20

11. Tighten the saddle cap fasteners evenly in several steps to 200 ± 20
foot pounds torque in proper sequence to achieve uniform bolt tension,
see Figure 8-20.
12. Install the tires.
13. Remove the support from the axles and lower the vehicle onto the ground.
14. Remove the wheel chocks.

EQUALIZING BEAM CENTER BUSHING
You will need:
■■ Vertical shop press with a capacity of at least 100 Tons.
■■ Center bushing tools – Receiving Tool No. 66086-112, Installation Tool No. 66086‑107 and

Removal Tool No. 66086-110, see Special Tools Section of this publication.
FIGURE 8-21

DISASSEMBLY
1. Remove the equalizing beam assembly
from the vehicle. Follow the equalizing
beam disassembly procedure in this
section.
DO NOT USE A CUTTING TORCH TO REMOVE
ANY FASTENERS OR BUSHINGS. THE USE
OF HEAT ON SUSPENSION COMPONENTS
WILL ADVERSELY AFFECT THE STRENGTH OF
THESE PARTS. A COMPONENT DAMAGED IN
THIS MANNER CAN RESULT IN THE ADVERSE
VEHICLE HANDLING AND POSSIBLE PERSONAL
INJURY OR PROPERTY DAMAGE.

2. Place the equalizing beam assembly in
a shop press with the center hub firmly
supported on the receiving tool or on the
press, see Figure 8-21.

Center Bushing
Removal Tool
Part No. 66086-110

Equalizing Beam Assembly
Center Bushing
Receiving Tool
Part No. 66086-112

3. Install the center bushing removal tool,
ensure it is centered on the center
bushing.
4. Push directly on center bushing removal tool until the center bushing is pressed out of the
equalizing beam bore, see Figure 8-21.
5. Inspect the beam bore.

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INSPECTION
After removing the center bushing, thoroughly inspect the beam bore. If damaged, replace
with a new equalizing beam. DO NOT attempt to re-bush or use an equalizing beam that has
been damaged.
FAILURE TO REPLACE AN EQUALIZING BEAM THAT HAS BEEN DAMAGED FROM BUSHING REMOVAL
CAN RESULT IN THE FAILURE OF THAT BEAM, LEADING TO ADVERSE VEHICLE HANDLING AND POSSIBLE
PERSONAL INJURY OR PROPERTY DAMAGE.

When installing new center bushings the following steps will minimize the chance of damaging
a new bushing:
1. Clean the bore of the equalizing beam with emery cloth or ball hone, removing any nicks or
metal buildup from bushing removal.
2. Measure the inside diameter of the equalizing beam center bore. The specification for the
inside diameter of the equalizing beam center bore on a new ULTIMAAX equalizing beam is
3.886" ± 0.003" (98.7 mm ± 0.1 mm), calculate the mean of any two measurements 90°
apart in the same plane, see Figure 8-22. If the mean is NOT within the specified range, replacement of the equalizing beam is required.
NOTE

Always use the bushing outer metal for pressing operations. Pressing on the bushings inner metal
may damage the bushing and require bushing replacement.
FIGURE 8-22

FIGURE 8-23

Lead in Chamfer Edge
in Equalizing Beam
Center Bushing Bore

Inside diameter of the equalizing beam center
bore on a new ULTIMAAX equalizing beam is
3.886" ± 0.003" (98.7 mm ± 0.1 mm)

FIGURE 8-24

ASSEMBLY
1. The equalizing beam bore may have a more substantial
lead in chamfer at one end of the bore than the other,
see Figure 8-23. Take advantage of the larger chamfer by
pressing in the new bushing from this end.
2. Place the equalizing beam in a shop press on the receiving tool or press. Support the beam squarely at the center
bore area to avoid distortion of the beam bore or bending
of the beam.
3. Lubricate the equalizing beam bore and the equalizing
beam center bushing outer metal sleeve with an NLGI#2
– EP (Extreme Pressure) grease, see Figure 8-24.
NOTE

The ULTIMAAX center bushing has voids that must be
positioned horizontally front and back, see Figure 8-25.

NOTE

The center bushing must be square with the equalizing beam
hub before pressing the center bushing into the beam. Center
bushings pressed in at an angle will damage the center bushing and the equalizing beam, see
Figure 8-26.

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FIGURE 8-25

FIGURE 8-26
Void

Horizontal
Centerline

Center Bushing
Outer Metal

Void

Equalizing Beam

CL

C
L

Verify the voids are
perpendicular to the
horizontal centerline
and the second locating hole
is on the bottom.

Center Hole

End Hub

Second Locating
Bottom Hole

C
L

Press the center bushing until the
center bushing outer metal sleeve is
centered in the end hub.

ALWAYS USE THE CENTER BUSHING OUTER METAL FOR PRESSING OPERATIONS. PRESSING ON THE
CENTER BUSHING’S INNER METAL WILL CAUSE DAMAGE TO THE CENTER BUSHING AND REQUIRE
CENTER BUSHING REPLACEMENT.

4. Install the center bushing installation tool, Part no. 66086-107, making sure the voids are positioned horizontally front and back and press in the new center bushing until the outer metal
sleeve is centered in the equalizing beam bore, see Figures 8-25 through 8-28.
5. Install the equalizing beam assembly to the vehicle. Follow the equalizing beam installation
procedure in this section.
FIGURE 8-27

FIGURE 8-28
Center Bushing Installation Tool
Center Hole
Bottom Hole
Center Bushing

Center Bushing
Installation Tool

Center Hole
Bottom Hole

Center Bushing
Outer Metal

Equalizing Beam
Center Hub

Verify both the center
hole and second
locator bottom hole
align properly

Center Bushing
Equalizing
Beam
Center Bushing
Hollow End

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