Oshkosh Load Span Tag Axle (LSTA)
SUBJECT: Axle Weldment Replacement Kit
& Installation Procedure
LIT. NO: TB−H807
DATE: July 2018
REVISION: C

INTRODUCTION
AXLE WELDMENT REPLACEMENT
KIT NO. 016816−00 CONTENTS
Description

Qty.

This publication is intended to assist with the identification and replacement of
axle weldment components on a limited number of Load Span Tag Axle (LSTA)
assemblies manufactured by Hendrickson and equipped on Oshkosh S−Series
front discharge mixers. The applicable LSTA assemblies were manufactured
between March 25, 2008 and January 30, 2017. The new production version
of the LSTA assembly (Hendrickson Part No. BAH13Z−XXK) is not affected.

Axle Weldment Subassembly
R−016191−00, Includes Kingpins

1

¾" Fastener Kit No. 016826−00

2

LSTA Assemblies

2
2
4
4
2
2
2
2
2
1

Manufactured between 03/25/2008 and 01/30/2017

Contents:
¾"−10 UNC x 4" Hex Cap Screw
¾"−10 UNC x 6½" Hex Cap Screw
¾"−10 UNC Nylon Locknut
¾" Washer
Cotter Pin
Stabilizer Spacer (Length 1.76")
½" Washer
½" Lock Washer
½"−13 x 1" Hex Cap Screw
7⁄8" Fastener Kit No. 016825-00
Contents:
7⁄8"−14 UNF x 9" Hex Cap Screw
7⁄8"−14 UNF Hex Nut
7⁄8" Washer
Medium Strength Threadlocker
Loctite® # 242

4
4
8
1

NOTE: All fasteners are Grade 8

Hendrickson Part No.

Oshkosh Part No.

Affected Serial Numbers

BAH13X−XXK

3724561

HAUX119723 through HAUX125012
HO0812030001 through HO1605044962

BAH13Y−XXK

4317305

HO1610114483 through HO1701090014

Hendrickson has learned the above−referenced axle weldment components
may develop slowly progressive cracks in the axle seat connections under
various service conditions. Such cracks will be clearly visible during routine
vehicle inspections. If this condition is allowed to progress over time, such
cracks could result in damage to the LSTA connections to the adjacent suspension trailing arms. Therefore, Hendrickson is offering to all applicable
owners, at no charge, an Axle Weldment Replacement Kit (No. 016816−00)
for affected LSTA assemblies. This kit includes the same new LSTA subassembly (including bolt−on cast axle seats) that is used in Part No. BAH13Z−XXK.

FIGURE 1

LSTA ASSEMBLY VERSIONS
BAH13X−XXK

BAH13Y−XXK

BAH13Z−XXK
New Production Version

Original Fabricated Axle Seat

Revised Fabricated Axle Seat

Bolt-on Cast Axle Seat

Axle Weldment Replacement Procedure for Oshkosh LSTA
A TECHNICIAN USING A SERVICE PROCEDURE OR TOOL WHICH HAS NOT BEEN RECOMMENDED BY
HENDRICKSON MUST FIRST SATISFY HIMSELF THAT NEITHER HIS SAFETY NOR THE VEHICLE'S SAFETY
WILL BE JEOPARDIZED BY THE METHOD OR TOOL SELECTED. INDIVIDUALS DEVIATING IN ANY MANNER
FROM THE INSTRUCTIONS PROVIDED WILL ASSUME ALL RISKS OF CONSEQUENTIAL PERSONAL INJURY
OR DAMAGE TO EQUIPMENT INVOLVED.
FIGURE 2

INSPECTION

Locate the Oshkosh vehicle identification tag and the Hendrickson
serial number tag (See Figure 2) to
determine whether an Oshkosh S−
Series front discharge mixer in your
fleet is equipped with an affected
LSTA.

Serial Number Tag located
under Stabilizer Bracket

AXLE REPLACEMENT

Stabilizer

Immediately contact Hendrickson Technical Services (phone: 800.660.2829 or e-mail:
liftaxletech@hendrickson-intl.com) to:
■■

■■
■■

Report whether any affected LSTA’s in your fleet show signs of any of the above−
referenced cracks or other damage that may develop in the axle seat connections or
adjacent components;
Order an Axle Weldment Replacement Kit (No. 016816−00); and
Advise whether your fleet may have sold to another party an Oshkosh S−Series front
discharge mixer equipped with an affected LSTA. (Please identify the names and
contact information of any/all such parties.)

DO NOT attempt to repair any cracks or other damage that may develop in the axle seat
connections or adjacent components. Hendrickson will work with Oshkosh and the vehicle
owner to coordinate the installation of an Axle Weldment Replacement Kit per the following
procedure. The replacement will take approximately six (6) hours to accomplish and will
be completed at no charge. Alternatively, the vehicle owner may install the Axle Weldment
Replacement Kit by following this procedure, and Hendrickson will reimburse the installation cost of such service kit.
DO NOT re−use, discard or destroy any affected axle weldment components removed from
the subject Oshkosh S−Series front discharge mixers. Rather, all such axle weldments
should be returned to Hendrickson. When your fleet orders an Axle Weldment Replacement
Kit, Hendrickson will make arrangements to pick up all affected axle weldments to be
replaced.
YOU WILL NEED:
■■ ½" Drive Impact Gun
■■ 11⁄8" and 15⁄16" Impact
Socket
■■ 7⁄16", 11⁄8" Open / Box−end
Wrench

■■ Grease

Gun and Gease

■■ Mallet
■■ Pliers
■■ Brass
■■ Jack

Punch
Stands

■■ Flat

Blade Screwdriver
■■ Torque Wrench Capable of
Reaching 570 ft. lbs.
■■ Digital Protractor
■■ Loctite® # 242

DISASSEMBLY
1.

Chock the drive wheels.

2.

Place the vehicle on a flat and level surface.
2

TB−H807

Axle Weldment Replacement Procedure for Oshkosh LSTA
3.

Remove air lines to brakes on LSTA.

4.

Remove the fenders, wheels/tires, and brake drums. Do Not remove the hubs.

5.

Keep the axle on truck trailing arms.

6.

Drop the trailing arms until axle is 12"−18" from the ground.

7.

Support the axle with jack stands.

THE STABILIZER IS EQUIPPED WITH A COIL SPRING THAT CONTAINS STORED ENERGY ONCE INSTALLED
ON THE AXLE. PRIOR TO AND DURING STABILIZER REMOVAL AND INSTALLATION, THE STABILIZER MUST
BE PROPERLY COMPRESSED AND RESTRAINED. FAILURE TO DO SO MAY ALLOW THE STABILIZER
TO RELEASE THE STORED ENERGY, RESULTING IN POSSIBLE DAMAGE TO COMPONENTS AND/OR
PERSONAL INJURY.
FIGURE 3

8.

Using the appropriate tools, restrain
stabilizers to restrain the stabilizer
coil springs.

9.

Remove the stabilizers with 1 1⁄ 8"
socket and wrench (See Figure 3).

10. Remove the cotter pin, castle nut
and tie rod with 15⁄16" impact socket
(See Figure 4).

Stabilizer

11. Remove the snap ring from the
Tie Rod
upper kingpin housing and knuckle NOTE
Wheel−end hub is not shown for illustration purposes only.
(See Figure 5).
12. Use the flat blade screw driver to remove the grease caps and zerk fittings from the
upper kingpin housing and lower knuckle.
FIGURE 4

FIGURE 5

Lightly tap the side of
the Ackerman arm to
loosen the tie rod end

Castle Nut

Cotter Pin

Snap Ring

Grease Cap
and
Zerk Fitting

FIGURE 6

13. Remove draw key (See Figure 6).
IF UPPER KINGPIN ASSEMBLY, KNUCKLE,
AND BRAKE ASSEMBLY ARE NOT SECURED,
THEY COULD MOVE/FALL AS THE KINGPIN
EXITS THE KINGPIN HUB. THIS COULD
RESULT IN PERSONAL INJURY.

14. Support and secure the knuckle
assembly to prevent movement
when removing the kingpin.
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3

Draw Key and
Flange Nut
NOTE
Wheel end hub is not shown for illustration purposes only.

Axle Weldment Replacement Procedure for Oshkosh LSTA
SERVICE HINT

Prior to disassembly of the upper kingpin assembly, knuckle and brake assembly, note the
orientation of the shims shown in Figure 9.
15. Remove the upper kingpin assembly, knuckle, wheel hub and brake assembly as one
unit (See Figure 9).
16. Use a brass punch and mallet to drive out the kingpin through the bottom knuckle
assembly (See Figure 9).
If the kingpin is frozen in the kingpin hub or difficult to remove, contact Hendrickson
Technical Services by phone 800.660.2829 or e-mail: liftaxletech@‌hendrickson-intl.com.

NOTE

17. Ensure to gather and re−use the thrust bearing and shims during re−assembly.
SERVICE HINT

Prior to disassembly of the axle from the trailing arms, note quantity and orientation of the
caster shims shown in Figure 8.
18. Remove the old axle from the trailing arms after BOTH kingpins are removed.

FIGURE 7

FIGURE 8

Upper Kingpin
Assembly

/8" — 14 UNF
U−bolt Hex Nut:
Initial torque only to
200 ± 10 ft. lbs.
Final torque will be
done later in the
Assembly procedures.

7

Trailing Arm
Flat Washer

/8" x 14 UNF x 9"
Hex Cap Screw

7

Caster shims
Knuckle
Draw Key
NOTE
Wheel end hub is not shown for illustration purposes only.

LSTA Axle
Weldment

ASSEMBLY
FIGURE 9

SERVICE HINT

1.

Slide the new axle weldment in
place.

2.

Install the flat washer onto the
7⁄8"−14 UNF x 9" hex cap screw.

3.

Insert the cap screw through axle
seat, shims, and trailing arms
(See Figure 8).

Place caster shims in the same
orientation as when removed. The
bolts should pass through the holes
in the caster shims − not the slots (if
present).
4.

Upper Kingpin Assembly

Thrust
Bearing

Shims
Draw Key

Kingpin
Hub

Brake
Assembly

Knuckle
Kingpin

Draw Key
Flange Nut
Tightening Torque
38 ± 7 ft. lbs.

Install 7/8” flat washer and hex NOTE
nut onto the cap screw and Wheel end hub is not shown for illustration purposes only.
loosely tighten the hex nut to
approximately 200 foot−pounds. DO NOT FULLY tighten at this stage; the final torquing of this joint is to be completed after verification of the caster angle at the end of
the assembly procedure.
4

TB−H807

Axle Weldment Replacement Procedure for Oshkosh LSTA
5.

After the new axle has been set in place and secured, slide the upper kingpin assembly, knuckle, hub and brake assembly in place (See Figure 9).

6.

Use the brass punch and mallet to drive the new kingpin up through the knuckle (See
Figure 10).

FIGURE 10

FIGURE 11
Ensure the numbers on the end
of the kingpin are facing up

Drive the new kingpin up through the knuckle
NOTE
Wheel−end hub is not shown for illustration purposes only.

NOTE

Ensure the numbers on the end of the kingpin are facing up as shown in Figure 11 and
that the draw key slot aligns with the draw key hole.
7.

Once through the knuckle, place the thrust bearing on the kingpin, between the
knuckle and kingpin hub. Continue driving the kingpin though the kingpin hub (See
Figure 12).

8.

Prior to when the kingpin goes into the upper kingpin housing, place the shims on the
kingpin. Place between the kingpin hub and upper kingpin housing (See Figure 13).

FIGURE 12

FIGURE 13
Upper
Kingpin
Assembly
Thrust
Bearing

Shims
Continue driving
the kingpin though
the kingpin hub

Kingpin Hub

NOTE
Wheel−end hub is not shown for illustration purposes only.

9.

Continue driving the kingpin into the upper kingpin housing.

10. Drive the kingpin up until the draw key slot lines up with the draw key hole.
11. Install the draw key and flange nut and tighten to

38 ± 7 foot−pounds of torque.

12. Install the grease caps, snap rings and zerk fittings.
13. Apply NLGI#2 grease to the kingpins using the zerk fittings.
14. Remove the wheel−cut stop bolt and lock washer.
15. Install the flat washer (supplied in kit) and re−install lock washer and the wheel−cut
stop bolt (See Figure 14). Tighten fastener to 25 to 30 foot−pounds of torque.
16. Use the appropriate tools to install both stabilizers with the original 1.76" spacers
(Part No 006645).
17. Install the ¾" stabilizer fasteners and "snug" the nuts (supplied in the kit). DO NOT
torque the nuts at this time.

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5

Axle Weldment Replacement Procedure for Oshkosh LSTA
18. Install the tie rod. Tighten tie−rod castle nut to 250 foot−pounds of torque, then
continue turning castle nut until a slot aligns with the cotter pin hole (See Figure 15).
FIGURE 14

½" 13 x 1" Stop Bolt
Lock Washer
Washer

19.
20.
21.
22.

Install the cotter pin (supplied in the service kit).
Ensure both lift axle wheel ends are in the straight ahead position.
Tighten the stabilizer fasteners to 98 ± 22 foot−pounds torque (See Figure 15).
Install the drums, wheels/tires and tighten the lug nuts to 475 foot−pounds torque per
the vehicle manufacturer’s specifications.
23. Install the fenders and tighten the 5⁄8"-11 x 4.0" long spiralock bolt fasteners to 210
foot−pounds torque.
24. Check toe and re−set to the Hendrickson recommended 1⁄16"-1⁄8" toe−in.
FIGURE 15
Tie Rod

Tie Rod Castle Nut
Tightening Torque 250 ft. lbs.
then continue to the next slot
aligns with cotter pin hole
Knuckle
Spacer
Stabilizer
¾" Stabilizer Locknut
Tightening Torque 98 ± 22 ft. lbs.

25. Lower LSTA and pressurize system to a DOWN EMPTY pressure setting.
26. Check caster angle with a Digital Protractor (See Figure 16).
FIGURE 16

Trailing Arm

Digital Protractor

LSTA Axle Weldment

Required Caster
Angle: 3.50 to 70
Ground

27. If the caster angle is between 3.5 and 7 degrees, remove each of the 7/8" nuts and washers
one at a time and apply Loctite® 242 to the threads of the bolt and then torque each nut to
570+/-10 foot−pounds (See Figure 17).

6

TB−H807

Axle Weldment Replacement Procedure for Oshkosh LSTA
28. If the caster angle is less than or greater than 3.5 to 7 degrees, follow these procedures:
a. Support the axle. Remove the LSTA mounting nuts and washers (See Figure 17).
Note:

Each caster shim is equal to two degrees. Oshkosh Part Number: 2073420
b. Install caster shims as necessary. Oshkosh recommends that a maximum of three (3)
shims be used in this application. If the caster angle cannot be achieved according to
these guidelines, please contact Hendrickson Technical Services (phone: 800.660.2829
or e-mail: liftaxletech@hendrickson-intl.com).
c. Re−install the LSTA's mounting washers and nuts and loosely tighten to 200 foot−
pounds. DO NOT perform final torque at this stage; the torquing of this connection is to be
completed after verification of the caster angle at the end of the assembly procedure.
d. Re−check caster angle. Repeat steps A, B and C if the caster angle is not between 3.5 and
7 degrees.
e. Once the proper caster angle has been achieved: one at a time, remove the 7/8" nuts,
apply Loctite® 242 to the threads of each bolt, replace the nut, and then torque each nut
to 570+/-10 foot−pounds (See Figure 17).

FIGURE 17

/8" −14 UNF
U−bolt Hex Nut
Final Torque:
570 ± 10 ft. lbs.
Apply Loctite® #242
to bolt threads prior
to re−installation of nuts.
7

Trailing Arm
Flat Washer

/8" x 14 UNF x 9"
Hex Cap Screw
7

Caster Shims

LSTA Axle
Weldment

TB−H807

7