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rHTECBlllCAL
®PROCEDURE
SOFTEK® I AIRTEK® Front
Suspension System for
FCCC Motorhome Chassis

SOFTEK®

SUBJECT: Service Instructions
LIT NO: 17730-253
DATE: November 2013
REVISION: F

1'4:Jii·''·'l"ihti
Section l

Introduction . ........................ 2

Section 9 Component Replacement ............ 47

Section 2 Product pescription .................. 2

Fasteners ........................... 47

Section 3 Important Safety Notice . .............. 5

Height Control Valve -AIRTEK ............ 47
Air Spring -AIRTEK .................... 48
Shock Absorber ...................... 50
Front Leaf Spring Frame Hanger .......... 51
Rear Shackle Frame Bracket ............. 52
Leaf Spring - SOFTEK .................. 54
Leaf Spring -AIRTEK ................... 57

Section 4 Parts List .......................... 1o
Section 5 Special Tools ....................... 18
Section 6 Towing Procedures . ................. 19
Section 7 Preventive Maintenance ............. 22
Component Inspection ................. 22
Clamp Group Re-Torque Interval ......... 23
Lubrication Intervals ................... 24
Kingpin Lubrication ................... 24
Tie Rod End Lubrication ................ 25
Tie Rod End Inspection ................. 26
Front Thrust Washer Inspection ........... 28
Rear Shackle Wear Pad Inspection ........ 28
Axle Wrap Liner Inspection (if equipped) ... 30
Shock Absorber Inspection .............. 30
Tire Inspection ....................... 32
Kingpin Bushing Inspection ............. 34
Steering Knuckle Inspection ............. 35

Section 8 Alignment & Adjustments ............ 36
Alignment Definitions .................. 36
Inspection Prior to Alignment ............ 38
Front Wheel Alignment. ................ 39
Steering Stop ........................ 41
Toe Setting .......................... 42
Spring Eye Re-Torque .................. 43

Spring Eye Bushings ................... 60
Bottom Axle Wrap (if equipped) .......... 60
Top Axle Wrap in Chassis (if equipped) .... 61
STEERTEK NXT I STEERTEK 1.5 Axle Removal. 63
STEERTEK Axle Removal ........ .' ....... 70
Steering Knuckle Disassembly ........... 74
Kingpin Preparation and Measurement .. 74
Kingpin Bushing Removal ............ 76
Steering Knuckle Bore Measurement .... 77
Kingpin Bushing Installation .......... 78
Kingpin Bushing Reaming .. '.......... 78
Kingpin Seal Installation ............. 80
Steering Knuckle Assembly .............. 80
Tie Rod End and Cross Tube ............. 82

Section l 0 Plumbing Diagram ................. 85
Section 11 Torque Specifications ............... 86
Section 12 Troubleshooting Guide .............. 94
Section 13 Front Wheel Alignment Specifications . 96
Section 14 Reference Material. ................. 97

Height Control Valve Verification -AIRTEK ... 44

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SOFTEK® I AIRTEK® for FCCC Motorhome Chassis
SECTION l

Introduction
This publication is intended to acquaint and assist maintenance personnel in the preventive
maintenance, service, repair, and rebuild of the following Hendrickson equipment as installed
on applicable FCCC Motorhome Chassis:
• SOFTEK® -An integrated steel spring front mechanical suspension with the
STEERTEK NXT I SlEERTEK 1.5 I STEERTEK axle.
• AIRTEK® -An integrated front· air suspension with the STEERTEK NXT axle.
• STEERTEK NXT I STEERTEK 1.5 I STEERTEK -A durable, lightweight, fabricated steer
axle assembly.
NOTE

Use only IHlHendrickson Genuine parts for servicing this suspension system.
It is important to read and understand the entire Technical Procedure publication prior to performing any maintenance, service, repair, or rebuild of the product. The information in this
publication contains parts lists, safety information, product specifications, features, proper
maintenance, service, repair and rebuild instructions for the SOFTEK/ AIRTEK Suspensions and
the STEERTEK NXT I STEERTEK 1.5 I STEERTEK axle.
Hendrickson reserves the right to make changes and improvements to its products and
publications at any time. Contact Hendrickson Tech Services for information on the latest version
of this manual at 1-866-755-5968 (toll-free U.S. and Canada), 1-630-910-2800 (outside U.S.
and Canada) or e-mail: techservice$@hendrickson-intl.com.

The latest revision of this publication is also available online at
www.hendrickson-intl.com.

SECTION 2

Product Description
FIGURE 2-1
SOFTEK Mechanical Suspension with STEERTEK NXT Axle
Capacity: 9,000 lb, 10,000 lb, 12,000 lb

AIRTEK Air Suspension with STEERTEK NXT Axle
Capacity: 10,000 lb

Introduction

2

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SOFTEK® I AIRTEK® for FCCC Moforhome Chassis
SOFTEK- is an integrated front mechanical suspension and steer axle system designed for
enhanced performance, durability and reduced maintenance. The advanced spring design of
the SOFTEK integrated front mechanical suspension and steer axle system produces increased
roll stability during cornering and crosswinds, creating a more stable platform. The design also
delivers exceptional ride and handling for driver and passenger comfort, proving ideal for bus
and motorhome applications.
Heavy-dufy parabolic leaf spring - optimized two-leaf spring design and premium
shocks result in an outstanding ride
Jounce bumper - integrated design enhances a smooth and comfortable ride
Optimized steering system performance - delivers an industry leading wheel cut of up
to 55 degrees resulting in a tighter turning radius and outstanding maneuverability
AIRTEK- is an integrated front air suspension and steer axle system designed to deliver driver
and passenger comfort, outstanding stability and extended vehicle life all in one package.
Hendrickson's AIRTEK integrated front air suspension and steer axle system combines simple,
functional design and state-of-the-art technology for superior ride, stability and handling. The
same smooth, comfortable ride that cradles passengers and drivers reduces vibration-induced
wear-and-tear to help extend overall vehicle and component life.
High volume air springs - support the vertical load and help produce a softer, more
comfortable ride
Leaf spring assembly - forms a torsion system with the box section axle to increase roll
stability
Optimized steering system performance - delivers an industry leading wheel cut of up
to 55 degrees resulting in a tighter turning radius and superior maneuverability
STEERTEK NXT Axle - Integrated into the SOFTEK/ AIRTEK system, the box-shaped axle design
provides a stiffer axle and resists torsional, longitudinal and vertical loads more effectively than
traditional I-Beam axles. Together with the front limbs of the leaf springs, the fabricated axle
beam forms a torsion system, enhancing roll stability characteristics and improving handling.
Axle clamp group - The clamp group consists of the top pad, %" U-bolts, washers and
nylon Locknuts.
Integrated Axle Seats - Integrated axle seats to improve ground clearance, reduce part
count, and simplify assembly.
Adjustable Tie Rod - To help maximize tire life, the tie rod easily adjusts toe-in/out.
Steering Knuckles - The steering and tie rod arms are integrated for increased strength
and reduced weight. The unique steering knuckle packaging delivers up to a maximum of
55° wheel cut. The two piece knuckle design makes replacing the kingpin bushings easier
by eliminating the need to remove the kingpins.

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3

Product Description

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SOFTEK® I AIRTEK® for FCCC Motorhome Chassis
TECHNICAL NOTES
1.

SOFTEK/ AIRTEK is approved for l 00% on-highway uses.All applications must comply with applicable Hendrickson specifications and must also be approved by the respective vehicle manufacturer
with the vehicle in its original. as-built configuration. Contact Hendrickson and the respective vehicle
manufacturer for approval of additional applications. This system has a 9,000, l 0,000 and 12,000
pound capacity. System capacity represents maximum loads on tires at ground level.

2.

STEERTEK NXT axle is available with 69.0" kingpin Intersection (KPI).

3.

STEERTEK NXT axle offers 5.36" axle beam drop heights. Axle beam drop is measured from the
kingpin intersection to the top of the axle spring seat (Top wrap).

4.

SOFTEK suspension weight includes frame hangers, main springs, bushings, shocks, upper shock
brackets and axle attachment hardware.

5.

AIRTEK suspension weight includes frame and shackle bracket assemblies, main springs, bushings,
air springs and air spring bracket, height control system, shocks, upper shock brackets and axle
clamp group.
STEERTEK NXT axle system weight is based on a 4.25" drop height and a 69.0" KPI axle. Weight
includes, the axle beam, knuckle/steering arm assemblies and tie rod assemblies.

6.
7.

8.

SOFTEK I AIRTEK is integral to and available exclusively with the STEERTEK NXT axle. This system
is anti-lock braking system (ABS) ready. STEERTEK NXT is compatible with most industry standard wheel ends and brakes, contact the vehicle or chassis and body manufacturer for more
information.
STEERTEK NXT axle product identification is etched on the center front of the axle beam, providing
the following information:
•
•

Axle part number: Identifies the features of the axle beam.
Axle assembly number: Identifies the complete assembly, which includes the steering knuckles and bracket assemblies.

FIGURE 2-2
Front view of axle showing approximate location of product identification.
Vehicles built AFTER March 2012

Approximate Location of
Product Identification

Vehicles built BETWEEN May 2010 and March 2012

Approximate Location of
Product Identification

Vehicles built PRIOR TO May 2010

Product Description

4

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SOFTEK® I AIRTEK® for FCCC Motorhome Chassis

SECTION 3

Important Safety Notice
Proper maintenance, service, and repair is important tor the reliable operation of the suspension. The procedures recommended by Hendrickson and described in this technical publication
are methods of performing such maintenance, service and repair.
All safety related information should be read carefully to help prevent personal injury and to
assure that proper methods are used. Improper servicing may damage the vehicle, cause personal injury, render it unsafe in operation, or void manufacturer's warranty.
Failure to follow the safety precautions in this manual can result in personal injury and/or
property damage. Carefully read and understand all safety related information within this pub·
lication, on all decals and in all such materials provided by the vehicle manufacturer before
conducting any maintenance, service or repair.

• EXPLANATION OF SIGNAL WORDS
Hazard "Signal Words" (Danger-Warning-Caution) appear in various locations throughout this
publication. Information accented by one of these signal words must be observed to help minimize the risk of personal injury to service personnel, or possibility of improper service methods
which may damage the vehicle or render it unsafe.
This is the safety alert symbol. It is used to alert you to potential personal injury
hazards. Obey all safety messages that follow this symbol to avoid possible injury or
death.
Additional 'Notes' or 'Service Hints' are utilized to emphasize areas of procedural importance
and provide suggestions for ease of repair. The following definitions indicate the use of these
signal words as they appear throughout the publication.

m

A

DANGER

INDICATES AN IMMINENTLY HAZARDOUS SITUATION, WHICH, IF NOT AVOIDED, WILL RESULT IN
SERIOUS INJURY OR DEATH.

A

WARNING

INDICATES A POTENTIAL HAZARDOUS SITUATION, WHICH, IF NOT AVOIDED. COULD RESULT IN DEATH
OR SERIOUS INJURY.

A

CAUTION

INDICATES APOTENTIAL HAZARDOUS SITUATION, WHICH, IF NOT AVOIDED, MAY RESULT IN MINOR OR
MODERATE INJURY.

NOTE

An operating procedure, practice condition, etc. which is essential to emphasize.

SERVICE HINT

A helpful suggestion, which will make the servicing being performed a little easier and/or faster.
Also note that particular service operations may require the use of special tools designed for
specific purposes.These special tools can be found in the Special Tools Section of this publication.
The torque symbol alerts you to tighten fasteners to a specified torque value. Refer to Torque
Specifications Section of this publication.

17730-253

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lmporfonf Safety Notice

SOFTEK® I AIRTEK® for FCCC Motorhome Chassis

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• SAFETY PRECAUTIONS

A

WARNING

FASTENERS
DISCARD USED FASTENERS. ALWAYS USE NEW FASTENERS TO COMPLETE A REPAIR. FAILURE TO DO
SO COULD RESULT IN FAILURE OF THE PART, OR MATING COMPONENTS, LOSS OF VEHICLE CONTROL
PERSONAL INJURY, OR PROPERTY DAMAGE.
LOOSE OR OVER TORQUED FASTENERS CAN CAUSE COMPONENT DAMAGE, LOSS OF VEHICLE
CONTROL PROPERTY DAMAGE, OR SEVERE PERSONAL INJURY. MAINTAIN CORRECTTORQUE VALUE
AT ALL TIMES. CHECK TORQUE VALUES ON A REGULAR BASIS AS SPECIFIED. USING A REGULARLY
CALIBRATED TORQUE WRENCH. TORQUE VALUES SPECIFIED IN THIS TECHNICAL PUBLICATION ARE
FOR HENDRICKSON SUPPLIED FASTENERS ONLY. IF NON HENDRICKSON FASTENERS ARE USED,
FOLLOW TORQUE SPECIFICATION LISTED IN THE VEHICLE MANUFACTURER'S SERVICE MANUAL.

A

WARNING

LOAD CAPACITY
ADHERE TO THE PUBLISHED CAPACITY RATINGS FORTHE SUSPENSIONS.ADD-ON AXLE ATTACHMENTS
(I.E. SLIDING FIFTH WHEELS) AND OTHER LOAD TRANSFERRING DEVICES CAN INCREASE THE
SUSPENSION LOAD ABOVE THE RATED AND APPROVED CAPACITIES WHICH CAN RESULT IN FAILURE
AND LOSS OF VEHICLE CONTROL POSSIBLY CAUSING PERSONAL INJURY OR PROPERTY DAMAGE.

A

WARNING

MODIFYING COMPONENTS
DO NOT MODIFY OR REWORK PARTS WITHOUT AUTHORIZATION FROM HENDRICKSON. DO NOT
SUBSTITUTE REPLACEMENT COMPONENTS NOT AUTHORIZED BY HENDRICKSON. USE OF MODIFIED,
REWORKED, SUBSTITUTE OR REPLACEMENT PARTS NOT AUTHORIZED BY HENDRICKSON MAY NOT
MEET HENDRICKSON'S SPECIFICATIONS, AND CAN RESULT IN FAILURE OF THE PART, LOSS OF
VEHICLE CONTROL POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE, AND WILL VOID ANY
APPLICABLE WARRANTIES. USE ONLY HENDRICKSON AUTHORIZED REPLACEMENT PARTS.

A

WARNING

SHOCK ABSORBERS
THE SHOCK ABSORBERS ARE THE REBOUND TRAVEL STOPS FOR THE LEAF SPRINGS. ANYTIME THE
FRONT AXLE ON AIRTEK/SOFTEK SUSPENSION IS SUSPENDED IT IS MANDATORY THAT THE SHOCK
ABSORBERS REMAIN CONNECTED. FAILURE TO DO SO CAN CAUSE THE AIR SPRINGS (IF EQUIPPED)
TO EXCEED THEIR MAXIMUM LENGTH, POSSIBLY CAUSING THE AIR SPRINGS TO SEPARATE FROM
THE PISTON, OR CAUSE A REVERSE ARCH IN THE STEEL LEAF SPRINGS, POSSIBLY RESULTING IN
PREMATURE STEEL LEAF SPRING FAILURE.

A

WARNING

REPAIR AND RECONDITIONING
THE REPAIR OR RECONDITIONING OF SUSPENSION OR AXLE COMPONENTS IS NOT ALLOWED, SEE
LABELS IN FIGURE 3-1, 3-2 AND 3-3. ANY AXLE COMPONENTS FOUND TO BE DAMAGED OR OUT OF
SPECIFICATIONS MUST BE REPLACED.ALL MAJOR HENDRICKSON COMPONENTS ARE HEATTREATED
AND TEMPERED. AIRTEK AND SOFTEK COMPONENTS CANNOT BE BENT, WELDED, HEATED, OR
REPAIRED WITHOUT REDUCING THE STRENGTH OR LIFE OF THE COMPONENT. FAILURE TO FOLLOW
THESE GUIDELINES CAN CAUSE LOSS OF VEHICLE CONTROL, POSSIBLE PERSONAL INJURY, DEATH,
OR PROPERTY DAMAGE AND WILL VOID APPLICABLE WARRANTIES.

A

WARNING

AXLE CAMBER
UNAUTHORIZED WELDING OR MODIFICATIONS CAN CAUSE CRACKS OR OTHER AXLE STRUCTURAL
DAMAGE AND RESULT IN LOSS OF VEHICLE CONTROL SEVERE PERSONAL INJURY OR DEATH. DO
NOT BEND, WELD OR MODIFY AXLE WITHOUT AUTHORIZATION FROM HENDRICKSON.
AXLE CAMBER IS NOT ADJUSTABLE. DO NOT CHANGE THE AXLE CAMBER ANGLE OR BEND THE AXLE
BEAM, SEE FIGURES 3-1, 3-2 AND 3-3; BENDING THE AXLE BEAM TO CHANGE THE CAMBER ANGLE CAN
DAMAGE THE AXLE AND REDUCE AXLE STRENGTH, WILL VOID HENDRICKSON'S WARRANTY AND CAN
CAUSE LOSS OF VEHICLE CONTROL POSSIBLY CAUSING PERSONAL INJURY OR PROPERTY DAMAGE.

A

WARNING

IMPROPER JACKING METHOD
IMPROPER JACKING METHOD CAN CAUSE STRUCTURAL DAMAGE AND RESULT IN LOSS OF VEHICLE
CONTROL SEVERE PERSONAL INJURY OR DEATH. DO NOT USE AXLE BEAM OUTBOARD OF AXLE
SPRING SEATS. REFER TO VEHICLE MANUFACTURER FOR PROPER JACKING INSTRUCTIONS, SEE
FIGURES 3-1, 3-2 AND 3-3.

Important Safety Notice

6

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SOFTEK® I AIRTEK® for FCCC Motorhome Chassis

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NOTE:
REPLACE ANY SAFETY DECALS THAT ARE FADED, TORN, MISSING, ILLEGIBLE, OR OTHERWISE DAMAGED.
CONTACT HENDRICKSON TO ORDER REPLACEMENT LABELS.
FIGURE 3-1

STEERTEK NXT Vehicles built AFTER March 2012
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INTEGWEO fll

Rear Shackle
Assembly

r,..

LH Upper Steering Knuckle '.lil~·
.
i
Kingpin Seal~

! : I :
·-...,i..j_ !

%" U-bolts

u

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Axle & Kingpin
Assembly

Composite Bearing \
:
LH Lower
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Steering Knuckle
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9
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Tie Rod Assembly

17730-253

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Component Replacement

SOFTEK® I AIRTEK® for FCCC Motorhome Chassis

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STEERTEK NXT I STEERTEK 1.5 AXLE REMOVAL
• Vehicles built AFTER May 201 O
AXLE DISASSEMBLY
Refer to Figures 9-26, 9-27 and 9-28 when replacing the components of the STEERTEK NXT I
STEERTEK 1.5 axle as shown.

A

WARNING

DO NOT USE ATORCH ON CLAMP GROUP BOLTS OR ANY OTHER PART OF THE SOFTEK I AIRTEK
SUSPENSION. IF THE CLAMP GROUP BOLTS WILL NOT COME LOOSE WITH AN IMPACT WRENCH, USE
A CUT OFF WHEEL AND CUT THE SHANK OF THE BOLT. THE USE OF ATORCH CAN CAUSE DAMAGE TO
CERTAIN SUSPENSION COMPONENTS THAT CAN RESULT IN THE LOSS OF VEHICLE CONTROL AND
POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE.
1. Place the vehicle on level floor.
2. Chock the wheels.
3. SOFTEK equipped vehicles - proceed to Step 6.

A

WARNING

PRIOR TO AND DURING DEFLATION AND INFLATION OF THE AIR SUSPENSION SYSTEM, ENSURE THAT
ALL PERSONNEL AND EQUIPMENT ARE CLEAR FROM UNDER THE VEHICLE AND AROUND THE SERVICE
AREA, FAILURE TO DO SO CAN CAUSE SERIOUS PERSONAL INJURY, DEATH, OR PROPERTY DAMAGE.
4. See additional Air Spring Cautions and Warnings in the Important Safety Notice Section of
this publication prior to deflating or inflating the air system.

A

WARNING

AIR SPRING ASSEMBLIES MUST BE DEFLATED PRIOR TO LOOSENING ANY CLAMP GROUP HARDWARE.