KINGPIN SEAL INSTALLATION
YOU WILL NEED:
■■

Kingpin Seal Driver / Remover Tool, refer to the Special Tools Section in this publication.

FIGURE 9-38
Ensure the lip of the
Kingpin Seal is facing
towards the axle.

FIGURE 9-39
Kingpin seal
bottoms out in the
kingpin bore

1. Place the steering knuckle assembly on a suitable workbench.
2. Lay the kingpin seal into the bore of the steering knuckle. Ensure the lip of the kingpin seal
faces toward the axle, see Figure 9-38.
3. Use a kingpin seal Driver / Remover tool and drive the seal firmly into the steering knuckle
assembly with a hammer.
4. Install the kingpin seal until it bottoms out in the kingpin bore, see Figure 9‑39.

STEERING KNUCKLE INSTALLATION
1. Clean the kingpin bores of the axle beam.
2. Install the thrust bearing assembly on the inner steering knuckle. The seal must face UPWARD
toward the beam. The top inner diameter will contact the bottom of the axle beam, see Figures
9-40 and 9-41.
WEAR GLOVES WHEN YOU INSTALL THE SHIMS. SHIMS HAVE SHARP EDGES THAT CAN CAUSE
SERIOUS PERSONAL INJURY.
FIGURE 40

Kingpin Seal MUST face
upward towards the axle
The top inner
diameter contacts
the bottom of
the axle beam

Top View

Bottom View

3. Place the knuckle onto the axle beam, see Figure 9-41.
4. Place a pry bar between the steering arm boss and the axle beam. Lift the knuckle and slide
the shim pack between the top of the beam and the steering knuckle, see Figure 9-42.

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Component Replacement

STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
FIGURE 9-41

FIGURE 9-42

Shim
Upper
Drawkey

Thrust Bearing
and Seal
Assembly

Axle
Lower
Drawkey
Knuckle Assembly

5. Align all the steering knuckle components within the kingpin bore. If the bores are not aligned,
the components will be damaged during kingpin installation.
6. Remove the pry bar.
7. Apply the multi-purpose grease onto the bottom half of the kingpin prior to kingpin installation
onto the steering knuckle.
VERIFY THAT THE DRAW KEY IS INSTALLED COMPLETELY OR THE LOCKNUT IS TIGHTENED TO 35 ± 5
FOOT POUNDS TORQUE. IF NOT INSTALLED CORRECTLY, THE KINGPIN AND THE AXLE BEAM WILL BE
DAMAGED.

8. Install the kingpin into the top of the knuckle and through the area where the shims are
located, see Figure 9-43 and 9-44. DO NOT force the kingpin through the upper kingpin bushing. Ensure the word TOP is facing up, see Figure 9-45.
FIGURE 9-43

FIGURE 9-44

FIGURE 9-45

Align
Kingpin

Installing
Kingpin

Upper
Drawkey

Verify the word
TOP is stamped
on the kingpin.

Lower
Drawkey

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STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
9. Rotate the kingpin and slide in until the two draw key slots align with the axle draw key bores,
see Figure 9-46 and 9-47.
10. If required, use a hammer and a brass drift to apply direct force to the kingpin for seating into
the lower steering knuckle bore, see Figure 9-46.
11. Seat the upper draw key into the front of the axle beam, see Figure 9-47.
12. Seat the lower draw key into the back of the axle beam by striking it with a hammer and drift,
see Figure 9-46. The draw keys must align with the slots of the kingpin.
13. Install draw key locknuts, Snug, DO NOT tighten torque until after the steering knuckle vertical
end play procedure is completed.
FIGURE 9-46

LOWER DRAW KEY

FIGURE 9-47

UPPER DRAW KEY

3 3/8" Draw Key
Part No.
75925-001
Front of the
Axle Beam

4¾" Draw Key
Part No.
75925-002
Back of the
Axle Beam

MEASURE STEERING KNUCKLE VERTICAL END PLAY
1. Turn the knuckle to the straight-ahead position.
2. Attach a dial indicator to the axle. Place the tip onto the top of the steering knuckle.
3. Set the dial indicator to zero, see Figure 9-48.
4. Use one of the following methods to measure the vertical clearance.
■■

Place a pry bar between the knuckle and the top of the axle center. Pry the knuckle up and
measure the vertical end play.

■■

Place a block of wood and a hydraulic jack under the bottom of the knuckle. Raise the
knuckle until the pointer on the dial indicator stops, see Figure 9-48.

5. Record dial indicator reading.
■■

If the knuckle binds or zero end play is measured, remove shims from the shim pack.

■■

If the reading is more than the correct specification shown in Table 9-2, add shims to the
shim pack.
FIGURE 9-48

TABLE 9-2

END PLAY SPECIFICATIONS
New or Rebuilt Axles: 0.001-0.010-inch (0.025-0.254 mm)
In-service Axles:
0.001-0.030-inch (0.025-0.762 mm)
6. Tighten upper and lower draw key locknuts
to 35 ± 5 foot pounds torque.

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Component Replacement

STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
GREASE CAP INSTALLATION
TAKE CARE WHEN YOU USE LOCTITE ADHESIVE TO AVOID SERIOUS PERSONAL INJURY. READ THE
MANUFACTURER’S INSTRUCTIONS BEFORE USING THIS PRODUCT. FOLLOW THE INSTRUCTIONS
CAREFULLY TO PREVENT IRRITATION TO THE EYES AND SKIN. IF LOCTITE® ADHESIVE MATERIAL GETS
INTO YOU EYES, FOLLOW THE MANUFACTURER’S EMERGENCY PROCEDURES. HAVE YOUR EYES
CHECKED BY A PHYSICIAN AS SOON AS POSSIBLE.

NOTE

If reusing a grease cap, ensure to apply the Loctite Straight Thread Sealant™ (STS) all around the
threads (apply to a minimum of 3 threads), see Figure 9-49.
1. Ensure Loctite STS is applied to a minimum of three grease cap threads (Note: New grease
caps have Loctite STS pre-applied).
2. Install the threaded grease caps onto the top of the knuckle.
3. Tighten the grease caps to

60 ± 10 foot pounds, see Figure 9-50.

4. Remove the bottle jack and continue assembling the wheel ends.
FIGURE 9-49

FIGURE 9-50

Apply Loctite STS to
a minimum of three
grease cap threads

Grease Cap
Tightening Torque
60 ± 10 ft. lbs.

STEERING ARM INSTALLATION
TAKE CARE WHEN YOU USE LOCTITE ADHESIVE TO AVOID SERIOUS PERSONAL INJURY. READ THE
MANUFACTURER’S INSTRUCTIONS BEFORE USING THIS PRODUCT. FOLLOW THE INSTRUCTIONS
CAREFULLY TO PREVENT IRRITATION TO THE EYES AND SKIN. IF LOCTITE ADHESIVE MATERIAL GETS INTO
YOU EYES, FOLLOW THE MANUFACTURER’S EMERGENCY PROCEDURES. HAVE YOUR EYES CHECKED BY
A PHYSICIAN AS SOON AS POSSIBLE.
FIGURE 9-51

1. Use a tap to remove old Loctite
adhesive from the internal
threads of the knuckle.

Steering Arm
Knuckle
Assembly
1" Hex Bolt
Tightening Torque
637 ± 13 ft. lbs.

2. Use new steering arm hex bolts
and apply Loctite 680 adhesive.
Ensure to cover at least half of
the thread area.
3. Insert the hex bolts through the
steering arm. Hand-start the
bolts into the knuckle assembly, see Figure 9-51.
4. Tighten the steering arm hex bolts to

Component Replacement

46

637 ± 13 foot pounds torque.

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STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
TIE ROD ARM INSTALLATION
1. Install a new O-ring on the bottom of the steering knuckle.
2. Use a tap to remove old Loctite adhesive from the internal threads of the knuckle.
3. Use new tie rod arm hex bolts and apply Loctite 680 adhesive. Ensure to cover at least
half of the thread area, see Figure 9-52.
4. Lubricate O-ring with grease and install tie rod arm on the bottom of the steering knuckle.
5. Insert the tie rod arm hex bolts through the tie rod arm and into the steering knuckle. Handstart the bolts into the knuckle assembly, see Figure 9-52.
6. Tighten the tie rod arm bolts to

487 ± 13 foot pounds torque.

7. Install the brake torque plate.
IMPORTANT NOTE

It is critical to apply Loctite to the three brake torque plate bolts to ensure that these bolts sustain
the proper torque requirement of steering knuckle assembly.
8. Apply Loctite Red 262 to the torque plate bolts prior to installation into the torque plate.
9. Tighten the toque plate bolts to
50 foot pounds torque.

400 ±

FIGURE 9-52
Knuckle
Assembly

10. Install the tie rod end into the tie rod arm,
see Figure 9-52.

Castle Nut
Cotter Pin

11. Tighten the castle nuts to
185 foot
pounds torque then rotate the castle nut
to the next castle slot and install cotter pin,
see Figure 9-52.
12. Install the drag link into the steering arm
and tighten to the vehicle manufacturer’s
­specifications.
13. Install wheel ends and tires.
14. Remove jack and safety stands.

Tie Rod End
Tie Rod Arm
7/8" Hex Bolt
Tightening Torque
487 ± 13 ft. lbs.

15. Grease steering knuckles with the vehicle on the floor.
16. Remove the wheel chocks.

TIE ROD ENDS AND CROSS TUBE
NOTE:

Hendrickson supplies different tie rod configurations. Prior to ordering, locate the part number on the tie rod tube, for additional information see Technical Bulletin SEU-0223 or contact
Hendrickson Tech Services.

DISASSEMBLY

FIGURE 9-53

1. Chock the wheels.
2. Position the steer axle tires straight ahead.
3. Remove the cotter pin and castle nut.
4. Lightly tap the side of the tie rod arm to loosen the tie
rod end from the tie rod arm, see Figure 9‑53.
5. Repeat to Steps 3 and 4 to remove the other tie rod
end.
6. Remove the cross tube and tie rod ends from the
vehicle.
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Lightly tap the side
of tie rod arm to
loosen the tie rod end

Component Replacement

STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
7. Mount the cross tube in a soft jaw vice.
8. Remove the hardware from the clamp on the cross tube.
9. Count the exposed threads on the tie rod end being replaced.
10. Remove the tie rod end from the cross tube.
DO NOT HEAT THE CROSS TUBE WITH A TORCH TO FACILITATE THE REMOVAL OF THE TIE ROD END. THE
USE OF SUCH HEAT CAN ADVERSELY AFFECT THE STRENGTH OF THE CROSS TUBE. A COMPONENT
DAMAGED IN THIS MANNER WILL RESULT IN LOSS OF WARRANTY, AND CAN RESULT IN THE AND LOSS
OF VEHICLE CONTROL, AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE.

11. If the opposing tie rod end is being replaced repeat Steps 8 through 10.
12. Inspect the cross tube for dents, cracks, or thread damage. Replace the cross tube if needed.

ASSEMBLY
1. Lubricate the new tie rod end threads with Anti-Seize.
NOTE

When installing the cross tube the thread direction of the tie rod ends are as follows:
■
A right hand threaded tie rod end will be installed into the right side tie rod arm.
■
A left hand threaded tie rod end will be installed into the left side tie rod Arm.
2. Install the new tie rod end into the cross tube, leaving the same amount of threads exposed
that were counted on the failed tie rod end prior to removal.
THE THREADED PORTION OF THE TIE ROD END MUST EXTEND PAST THE SLOTS INTO THE TIE ROD
CROSS TUBE, SEE FIGURE 9‑54. FAILURE TO DO SO CAN CAUSE COMPONENT DAMAGE, LOSS OF
VEHICLE CONTROL AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE.
FIGURE 9‑54

5/8" Tie

Rod Clamp Bolt
It is critical to check the 5/8" tie rod clamp bolt
head location to verify the clamp fasteners have
sufficient clearance away from the lower shock
mount at full wheel cut. The fasteners must not
contact the lower shock mount.

Tie Rod Cross Tube Slots
It is critical to have the threaded
portion of the tie rod end extend past
the slots in the tie rod cross tube.

Threaded Portion
of the Tie Rod End

5/8" Tie

Rod Clamp Locknut
Tightening Torque 68 ± 7 ft. lbs.

IT IS CRITICAL TO CHECK THE 5⁄ 8" TIE ROD CLAMP BOLT HEAD LOCATION TO VERIFY THE CLAMP
FASTENERS HAVE SUFFICIENT CLEARANCE AWAY FROM THE LOWER SHOCK MOUNT AT FULL WHEEL
CUT. THE FASTENERS MUST NOT CONTACT THE LOWER SHOCK MOUNT. FAILURE TO DO SO CAN
CAUSE ONE OR MORE COMPONENTS TO FAIL CAUSING LOSS OF VEHICLE CONTROL AND POSSIBLE
PERSONAL INJURY OR PROPERTY DAMAGE.

3. Replace the opposing tie rod end if necessary by repeating Steps 1 and 2.
DO NOT HEAT THE CROSS TUBE WITH A TORCH TO ROTATE THE CROSS TUBE IN THE TIE ROD END. THE
USE OF SUCH HEAT CAN ADVERSELY AFFECT THE STRENGTH OF THE CROSS TUBE. A COMPONENT
DAMAGED IN THIS MANNER WILL RESULT IN LOSS OF WARRANTY, AND CAN RESULT IN THE LOSS OF
VEHICLE CONTROL, AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE.

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STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles
4. It is critical that the cross tube rotate in the opposing tie rod end, even if it is not replaced.
5. Install the tie rod end into the tie rod arm.
6. Tighten the castle nuts to 185 foot pounds, torque then rotate the castle nut to the next
castle slot and install cotter pin.
7. Grease the tie rod ends. Refer to the Lubrication Chart for required lubricant in the Preventive
Maintenance Section of this publication.
8. Set the toe, refer to the Toe Adjustment Procedure in the Alignment & Adjustments Section of
this publication.

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STEERTEK NXT High Capacity Steer Axle System for Autocar® ACX-XPEDITOR™ Vehicles

SECTION 10

Alignment Specifications
STEERTEK NXT High Capacity
FRONT SUSPENSION ALIGNMENT SPECIFICATIONS
CAMBER1

DESIGN SPECIFICATION

RANGE
MINIMUM

MAXIMUM

LEFT

0.0°±1.0°

-1.0°

+1.0°

RIGHT

-0.25°±1.0°

-1.25°

+0.75°

CROSS

0.0°

—

+2.0°

CAMBER NOTES:
1

The camber angle is not adjustable. DO NOT bend axle or otherwise try to adjust camber. If found out of ­specification, notify
Hendrickson Tech Services for further information.

CASTER1,2

DESIGN SPECIFICATION

RANGE
MINIMUM

MAXIMUM

LEFT

3°±1.0°

+2°

+4°

RIGHT

3°±1.0°

+2°

+4°

0.0°

—

+1.5°

CROSS³
CASTER NOTES:
1

Caster is determined with the vehicle at specified ride height for air suspension or at rated load for mechanical suspension systems.
It is critical that the vehicle front and rear ride height is within specifications prior to performing a caster measurement or adjustment.
See Hendrickson ride height s­ pecifications and procedure.

2

In most cases actual vehicle caster is defined with the frame rails at zero slope. Refer to the vehicle manufacturer’s specifications
for correct frame rail slope. (Both the alignment surface and the vehicle’s frame rails should be level during execution of alignment
procedures). For vehicles with a positive frame rake (higher in rear) add the frame slope (in degrees) to the caster reading to
determine true vehicle caster.

3

The Cross caster angle is not adjustable – DO NOT bend axle or otherwise try to adjust cross caster. If found out of specifications
notify Hendrickson Tech Services for further information. Changes to caster can be attained by using caster shims as p­ rovided by the
vehicle manufacturer or chassis and body manufacturer. Caster shims must match, side to side, to reduce uneven loading to the
suspension components. The use of two different angle caster shims will not correct cross caster.

4

Example of caster adjustment: 4.5º RH / 5º Left Hand would require one, 1.0 shim on each side to increase caster and achieve
5.50° Right Hand / 6.00° Left Hand, which is in specification. DO NOT attempt to use uneven shims.

Hendrickson recommends the following TMC2 practices:

RANGE

DESIGN SPECIFICATION¹

TOTAL TOE²