APPLICATION
GUIDE

HENDRICKSON AIR DISC BRAKES
LIT NO: L1225
DATE: September 2018

REVISION: G

TABLE OF CONTENTS
Introduction............................................................... 2

Height Control Valve Requirements............................. 6

Purpose.................................................................... 2

TRLAXLE® Non-Integrated Axle Brake Caliper Position.... 7

Important Notice........................................................ 2

Wheel and Valve Stem............................................... 7

Questions.................................................................. 2
Changes to Guidelines............................................... 2
Air Disc Brake Option................................................. 3
Brake Ratings............................................................ 3
Air Disc Brake Ordering Guide /
Application Release Form........................................... 3

Trailer Brake Air Line Routing...................................... 7
Air Disc Brake Wheel-End System Options................... 8
Hendrickson ADB Options Matrix................................. 8
Air Disc Brake Warranty.............................................. 9

Suspension and Axle Availability................................. 4

Air Disc Brake Package Weights Compared
to Drum Brakes........................................................ 10

Suspension and Axle Specification Requirements........ 5

Air Disc Brake vs. Drum Brake Weight Comparison..... 10

Additional Component Requirements......................... 5

Closing................................................................... 10

APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

INTRODUCTION

QUESTIONS

Hendrickson presents this publication to aid in
understanding Hendrickson's Air Disc Brake (ADB)
product offering and application requirements.
Hendrickson offers ADB packages for several wheelend systems to meet virtually any application or
technology requirement.

For answers to questions concerning these guidelines,
for information not covered in these guidelines or to
request a Hendrickson Trailer Ordering Guide, contact:
Hendrickson Trailer Commercial Vehicle Systems
2070 Industrial Place SE
Canton, OH 44707-2641
Telephone: 866-743-3247 (866-RIDE-AIR)
Website: www.hendrickson-intl.com

PURPOSE

The purpose of this document is to provide original
equipment manufacturers (OEMs) of medium and
heavy-duty vehicles with application guidelines for
Hendrickson Air Disc Brakes.

CHANGES TO GUIDELINES

These guidelines are subject to change at any time
without prior notice at the discretion of Hendrickson.
To get the most up-to-date version of these guidelines
visit www.hendrickson-intl.com.

The descriptions and specifications contained in this
publication are current at the time of printing.
Hendrickson reserves the right to discontinue or
modify its models and / or procedures and to change
specifications at any time without notice.
Any references to brand names in this publication
are made as an example of the types of tools and
materials recommended for use and should not be
considered an endorsement. Equivalents may be used.

IMPORTANT NOTICE

Hazard signal words (such as Warning or Caution)
appear in various locations throughout this publication.
Information accented by one of these signal words
must be observed at all times.
Additional notes 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.
WARNING: INDICATES HAZARDS OR UNSAFE
PRACTICES WHICH COULD RESULT IN
SEVERE PERSONAL INJURY OR DEATH.
CAUTION: Indicates hazards or unsafe practices
which could result in damage to
equipment or minor personal injury.

R NOTE:

Additional service information not
covered in the service procedures.

2

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APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

AIR DISC BRAKE OPTION

BRAKE RATINGS

Hendrickson offers the following ADB systems
for 17.5"*, 19.5", 22.5" and 24.5" wheels:

Hendrickson MAXX22T, WABCO PAN22-1, Knorr / Bendix
ADB22X-LT, Haldex ModulT (DBT22LT), Haldex ModulX
(DB22), WABCO PAN17 and WABCO PAN19 each use a
specific brake pad lining and brake chamber tuned for
each respective ADB package to achieve the desired
brake rating.

1. Hendrickson MAXX22T ™
This system uses a 415mm diameter rotor that
is compatible with 22.5" or 24.5" wheels.

For a complete list of all ADB brake rating certifications
for FMVSS-121 (USA), CMVSS-121 (Canada) and
ECE R13 (Europe), please reference Hendrickson
literature number L809 – Consolidated Certificate
of Compliance for Air Actuated Brakes. This
document is available on Hendrickson’s website
at www.hendrickson-intl.com.

2. WABCO PAN22-1
This system uses a 430mm diameter rotor that
is compatible with 22.5" or 24.5" wheels and will
fit dual or wide base tires.
3. Knorr/Bendix ADB22X-LT
This system uses a 430mm diameter rotor that
is compatible with 22.5" or 24.5" wheels and
will fit dual or wide base tires. Knorr/Bendix ADB22X
is not approved for dolly applications.

AIR DISC BRAKE ORDERING GUIDE /
APPLICATION RELEASE FORM

To order ADB packages from Hendrickson, customers
are required to complete and submit an ordering
guide. In some cases, an application approval is also
required using one of the ADB approval methods
(listed below):

4. WABCO PAN19
This system uses a 375mm diameter rotor that
is compatible with 19.5" wheels and will
fit dual or wide base tires.

A. Pre-Approval (per disc brake manufacturer
requirements)

5. Haldex ModulT (DBT22LT)

B. Online Approval

This system uses a 430mm diameter rotor that is
compatible with 22.5" or 24.5" wheels and will fit
dual or wide base tires.

C. Waiver (found on the last page of the product
ordering guide)

6. Haldex ModulX (DB22)

D. Application form (found on the last page
of the product ordering guide)

This system uses a 430mm diameter rotor that is
compatible with 22.5" or 24.5" wheels and will fit
dual or wide base tires.

This application approval is required by our ADB
suppliers who use this information to fully understand
the trailer application as well as the brake balancing
characteristics between the tractor and trailer.

*Reference WABCO PAN17 Application Guide, L1272, for 17.5"
wheels.

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R NOTE:

3

The application approval is not required
for the Hendrickson MAXX22T system.
The MAXX22T is approved for use in
on-highway applications using the
approved brake ratings.

APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

SUSPENSION AND AXLE AVAILABILITY

R NOTE:

The table below provides a summary of the suspension
systems and axle models available with air disc brakes.

Hendrickson MAXX22T™, WABCO PAN22-1,
Haldex ModulT (DBT22LT) ModulX (DB22)
or WABCO PAN19 must be specified for all
dolly applications. Bendix does not approve
the use of the ADB22X in dolly trailer
applications.

HENDRICKSON SUSPENSIONS AND AXLES AVAILABLE WITH ADB
INTRAAX

SUSPENSION / AXLE MODELS

AVAILABILITY

AANT 23K
AANLS 20K / AANL 23K
AAT 23K, 25K, 30K
AAL 23K, 25K, 30K
AAEDL 30K* / AAEDT 30K*

Requires unique HCV
Requires rear mounted shocks and unique HCV
ADB OK without SURELOK® — requires unique HCV
Requires rear mounted shocks
Requires rear mounted shocks

AAZNT 23K, 46K
AAZNT 69K
AAZL 23K, 46K

Requires unique HCV
ADB OK
Not available

ULTRAA-K® UTKNT 40K**

ADB OK

HKANT 23K, 40K, 46K**
HKANT 69K23**
HKAT 50K**
HKAT 69K25, HKARL**
HKANL, HKAL**

Requires unique HCV
ADB OK
ADB OK without SURELOK — requires unique HCV
ADB OK without SURELOK
Not available

CXSL 25K

Not available

HT250YB
HT250T
HT230T, HT300T
HT250U, HT250UB
HT190U, HT250US, HT300US
HT250Y, HT250YS, HT300YB

Call for application approval
Brake chambers in forward position only
ADB OK
Call for application approval
Not available
Not available

TRLAXLE — ½", 5/8", 5/8" HD wall
TRLAXLE — ¾" wall

ADB available on limited tracks
Not available

TIREMAAX CP, TIREMAAX PRO

ADB OK

®

INTRAAX®-SP

ULTRAA-K®
VANTRAAX

®

CONNEX™-ST
HT SERIES
™

TRLAXLE®

TIREMAAX®
* Not available with Hendrickson MAXX22T.
** Not available with WABCO PAN19.

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APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

SUSPENSION AND AXLE
SPECIFICATION REQUIREMENTS

ADDITIONAL COMPONENT
REQUIREMENTS

The chart below outlines the axle tracks available for
suspension and axle systems equipped with ADBs.
MODELS
VANTRAAX®

AXLE TRACK
71.5", 77.5" and 83.5"

INTRAAX®
TRLAXLE®

71.5", 73", 75.5", 76.5", 77.5",
83.5" and 85"

ULTRAA-K®

77.5"

Hendrickson requires all ADB equipped suspensions
and axles to be fitted with dust shields and ABS
sensors. Whereas ABS sensors for drum brakes are
“right angle” 90-degree shaped, sensors for ADB are
“straight” shaped. Depending on caliper brand, ABS
sensing may be done by hub-mounted tone rings or
rotor-mounted tone rings.

"Straight" ABS Sensor for ADB
"Straight" ABS Sensor for ADB

90-Degree ADB Sensor for Drum Brakes

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APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

HEIGHT CONTROL VALVE
REQUIREMENTS

Conventional HCV Mounting for Drum Brake

Some ADB-equipped suspensions require a unique
height control valve (HCV) mounting kit. These
HCV kits are unique because of the lower mount
connection. On drum brakes, the HCV usually mounts
to the brake chamber bracket. With ADB, there is no
brake chamber bracket, so the HCV mounts to the
axle using a band clamp arrangement. Suspension
models that require a unique kit are referenced in
the chart below.
INTRAAX®
AANT 23K
AAT 23K/25K/30K
AANL 23K
AANLS 20K
VANTRAAX®
HKANT 23K/40K/46K
HKAT 50K

R NOTE:

INTRAAX -SP
®

AAZNT 23K/46K
Refer to Hendrickson literature number
L1024 - Height Control Valves or
L1182 - Controls Parts Catalog on the
Hendrickson website for more information.

Additional restrictions may apply;
please contact Hendrickson Customer
Service for assistance.

The following drawings show the difference between
typical ADB suspension HCV mounting kits versus drum
brake suspension HCV mounting kits.
HCV Mounting for ADB

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APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

TRLAXLE® NON-INTEGRATED AXLE
BRAKE CALIPER POSITION

These can also be found at the bottom of page 7
of L964 Hendrickson Trailer Axles Ordering Guide.

Brake caliper position is an important piece of information
Hendrickson needs to fully configure an ADB-equipped
non-integrated suspension or axle. Customers must
select the brake caliper position as shown in the drawings
below to ensure proper orientation of the brake chamber
per the specification ordered by the end user.

CAUTION: For underslung mechanical
suspensions, call Hendrickson
and the suspension supplier.

R NOTE:

A. For top-mount mechanical suspensions or
top-mount air suspensions with brake chamber
to the REAR of the axle.

For all caliper positions shown, the tire
inflation holes are located on top dead
center of axle when suspension is at
ride height. Customer should verify
brake chamber clearance at the entire
suspension travel range. On Figure C,
the shock cannot be mounted in front
of the axle on underslung suspensions
due to interface with the brake chamber.

WHEEL AND VALVE STEM
WARNING: Great care must be taken in selecting
combinations of wheel and valve stem
products that are compatible with
ADB. Improper wheels or valve stems
can interfere with air disc brakes and
cause rapid tire deflation, component
damage, a loss of vehicle control,
PROPERTY DAMAGE OR SEVERE
PERSONAL INJURY. Use only wheels
and valve stems that provide proper
running clearance with air disc brakes
equipped on the suspension. Each
brake manufacturer has compiled a
list of approved wheel and valve stem
combinations that can be selected
during the approval process. If a wheel
and valve stem combination is not
available, please contact the brake
manufacturer for approval. You may
also contact the vehicle or brake
manufacturer to determine replacement wheels and valve stems
approved for the application.

B. For top-mount air suspensions with brake
chamber to the FRONT of the axle.

C. For low-ride / underslung air suspensions
with brake chamber to the FRONT of the axle.

TRAILER BRAKE AIR LINE ROUTING
WARNING: Great care must be taken when installing
brake chamber air lines. Brake air lines
must be installed to ENSURE FREE
MOVEMENT of the caliper over its entire
stroke. Attach brake hose to the brake
chamber according to chamber
manufacturer's specifications.
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APPLICATION GUIDE — HENDRICKSON AIR DISC BRAKES

AIR DISC BRAKE WHEEL-END
SYSTEM OPTIONS

Conmet PreSet ADB Wheel-End Systems
Hendrickson offers the Conmet PreSet wheel-end
system with two options:

Hendrickson offers ADB packages in combination with
several wheel-end systems:

1. PreSet Aluminum Hub
2. PreSet Ductile Iron Hub

• Standard service wheel-end
• HXL Hendrickson Extended-Life wheel-end
• Conmet PreSet wheel-end

The Aluminum PreSet hub is available on both WABCO
PAN22-1 ADB, Haldex Modul T (DBT22LT) and Knorr
/ Bendix ADB22X-LT ADB packages. The ductile iron
PreSet hub is only available on the Knorr / Bendix
ADB22X-LT package on an HP spindle.

The specific options for each are shown in the
Hendrickson ADB Options Matrix, listed below.
HXL7® Hendrickson Extended-Life 7-Year System™
is an industry exclusive system that combines
Hendrickson’s engineering and manufacturing
expertise with high-performance wheel-end
components to create a system that delivers reliability
and performance mile after mile.

For USA and Canada on-highway applications, the
Conmet PreSet ADB wheel-end systems carry a limited
five-year parts and one-year labor warranty on the hub,
seal and bearings, excluding all normal wear. For
areas outside the USA and Canada, Conmet PreSet
ADB wheel-end systems carry a limited one-year parts
and labor warranty on the hub, seal and bearings,
excluding all normal wear. You may contact Conmet
directly for ADB wheel-end warranty administration.

HXL5® Hendrickson Extended-Life 5-Year System™
and HXL3® Hendrickson Extended-Life 3-Year
System™ are wheel-end packages, like HXL7, that
offer the convenience of a single supplier for
support and peace of mind from the most trusted
name in the trailer industry.

HENDRICKSON ADB OPTIONS MATRIX
ADB OFFERING

Hendrickson MAXX22T™ or Wabco PAN22-1,
Knorr-Bendix ADB22X-LT, Haldex ModulX,
Haldex ModulT or WABCO PAN19**

ADB22X-LT

ADB22X-LT,
PAN22-1 or
Haldex
ModulT

Wheel-End Package

Standard 1
Year*

HXL3®

HXL5®

HXL7®

Conmet PreSet

On-Highway
Off-Road

1 Year
1 Year

3 Year
1 Year

5 Year
3 Year

7 Year
3 Year