B

B-B

KEY
1 - Wheel Hub
2 - Splined Disc Rotor
3 - Intermediate Elements (Spacers)

Figure 89 – Installing Intermediate Elements
(Spacers)

B
KEY
1 - Wheel Hub
2 - Bendix® Splined Disc® Rotor
3 - Intermediate Element (Spacer)
4 - Spring Element (Fastener), including retention clips

Figure 87 – Rotor with Cross-Section View

Figure 90 – Intermediate Elements (Spacers
Installed)
hub does not exceed 0.015 in. (0.4 mm). If a gap is
found that exceeds this maximum value, verify the
installation of new intermediate elements (spacers).
Replace the wheel hub if the excess gap cannot
be corrected with proper installation of new rotor
retaining hardware.
4.7.11 Install the ten new spring elements included in the
kit in an evenly-distributed cross-pattern sequence.
Torque to 22.1 ft-lbs (30 N•m).

Figure 88 – Rotor Installation

ROTOR INSTALLATION

4.7.10 See Figures 87 through 91. Place the rotor into
position on the hub. Install the new intermediate
elements (spacers) as shown in Figure 89. With
all the intermediate elements (spacers) correctly
inserted into position, verify that the gap between
the intermediate elements (spacers) and the wheel
42

4.7.12 Where the tone ring was removed during step 4.7.7,
reinstall the tone ring. Use a professional grade
fastener compound, such as Loctite® Blue 242®, on
the fasteners. Torque to 19-22 in-lbs (2.1-2.5 N•m).
4.7.13 Reinstall the hub rotor assembly using a new
high-temperature wheel seal, following the vehicle
manufacturer’s instructions.

5.0 U-SHAPE ROTOR INSTALLATION
Following industry standards, clean and inspect the hub
before installing the rotor. Install the new rotor to the hub,
using the cap screws included in most kits. (NOTE: the
cap screws have pre-applied thread-locking compound).
Torque to 200-225 ft-lbs (271-305 N•m). See Figure 92 for
the suggested torque sequence.

Figure 91 – Fasteners Installed

NOTE: Because of the many different installations,
fasteners may not be provided in this kit. In these cases,
obtain fasteners from the vehicle manufacturer. Install per
vehicle manufacturer recommendations for torque and
retention compound (e.g. Thread-locking compound).

4.7.14 Reinstall the air disc brake (See Section 4.3).
Supporting the air disc brake by all necessary
means, attach the brake to the anchor plate
using six bolts and washers as required (Bendix
recommends the original bolts not be re-used).
Torque to vehicle manufacturer's specifications.
If torque values and bolts are not specified by the
vehicle manufacturer, then torque according to
the chart shown in Table 4. Be sure to select bolts
with the same thread pitch, length, and grade as
originally provided from he vehicle manufacturer.
4.7.15 Reinstall the brake pads (See Section 4.2).

Suggested Rotor
Torque Sequence for 10
fastener hubs. For other
fastener configurations,
please see the vehicle
or axle manufacturer’s
specifications.

Figure 92 – Torque Sequence

43

SECTION SIX: TROUBLESHOOTING PROCEDURE FLOWCHART
For additional troubleshooting information, refer to Bendix® Air Disc Brake Caliper and Rotor Inspection Procedure,
BW7634, on B2Bendix.com.
Air Disc Brake
Inspection
Follow safe maintenance practices; chock wheels.
Release the spring brake and cage the brake. Or, if unable
to release the brakes with air, then cage the brakes.

Raise the axle, spin
the wheel by hand.

Does
the wheel turn
smoothly?
NO

NO

YES

Is the
spring brake
fully/partially
applied?

Check
running
clearance (3.1)
- OK?

YES

NO
Check
running
clearance (3.1)
- OK?
YES

NO

Check
adjuster (3.2)
- OK?

YES

YES

Check
caliper
guidance (3.5)
- OK?

YES

Check
adjuster (3.2)
- OK?

Drain the air pressure
from the system. Restart
test after caging spring
brakes.
NO

NO

Replace caliper/
carrier assembly
(4.3).

Check
caliper
guidance (3.5)
- OK?

NO
YES
Replace caliper/carrier
assembly (4.3).

NO

Replace the
guide pins (5.6) OR
replace caliper/carrier
assembly (4.3).

Tightness not
due to air disc
brake. See vehicle
manual.

Figure 14 – Troubleshooting Bendix ® Air Disc Brakes
44

YES

Disc
brake
OK.

YES

Check
pad and
rotor wear (3.33.4)
- OK?

NO

Replace
components
as needed with
genuine
Bendix® parts.

Component
(Item / Condition)

Investigation

Specs

See
Section(s)

BENDIX ® ADB22X ® TROUBLESHOOTING GUIDE
What To Replace

Guide Pins

Boots and Seals

Disc Brake Pads

Consumable Items: These are considered to be normal wear items and should be repaired as part of regular
preventive maintenance.
Pads must be replaced when they reach
0.125 in. (3.2 mm) of friction material.

A

Worn

Measure the thickness of the
remaining friction material.

B

Uneven
wear on
single pad

Measure the thickness of the
total pad in at least two (2)
places at the top and two (2)
places at the bottom, at least
1/2 in. from the edge.

The average difference of top vs. bottom or
left vs. right should be no greater than
0.080 in. (2 mm).

3.3.2

C

Uneven
wear on
inboard vs.
outboard

Measure the pad thickness as
described for Item B above,
but also check guide pin wear
and slide-ability.

Average difference inboard to outboard should
be no greater than 0.138 in. (3.5 mm).

3.3.3

D

Surface
damage

Inspect for minor chips near
the edge and cracks on the
face (permitted) vs. major
sections damaged or missing.

See Figure 24.

3.3.3

E

Tears and
cuts

Inspect the tappet and guide
pin boots for cuts, cracks, and
tears.

Any damage must be repaired.

3.5.4
and
3.6.2

Melting

Inspect as Item E above,
but also check the running
clearance before removing the
brake pads.

Any damage must be repaired.

2.2
and
3.6.1

G

Binding

With the pads removed, the
caliper should move freely by
hand. Loosen and re-torque
the caliper to anchor plate
bolts per the OE spec and
procedure, if binding.

See Figure 25 (slide) and Table 4 (torque).

H

Excessive
play

Feel for excessive play
between the caliper and the
carrier.

See Figure 26.

F

Worn

Rotors

I

Measure the rotor thickness
with a long jaw caliper.

3.3

3.5.1
and 4.3

3.5.2

Thickness must be greater than 1.46 in.
(37 mm).
3.4

J

Surface
damage

Minor cracks and grooves
are acceptable, but check for
cracks over the inside and
outside edges.

See Figure 12 for surface details.

Replace the pads on both
sides of the worn axle.

Replace the pads on both
sides of the worn axle
and replace the guide
pins as needed.

Replace the pads on both
sides of the worn axle.

Replace the damaged
boots and replace
the resultant internal
corroded guide pins as
needed.
Replace worn guide pins
as needed. If guidance
system binding still occurs,
replace caliper/carrier
assembly. Replace anchor
plate if new caliper/carrier
assembly does not resolve
issue.
Replace the worn guide
pins as needed.
Refer to the OEM
recommendations for
non-Bendix® rotors. For
Bendix rotors, replace the
rotors on both sides of
the axle.
Refer to the OEM
recommendations for
non-Bendix rotors. For
Bendix rotors only,
replace the rotor that is
damaged.

Calipers

Non-Serviceable: These are non-serviceable items and pending warranty terms; these issues may be covered under
warranty.
K

Adjuster
not rotating

L

Adjuster
too tight,
dragging
brake

If the second shear adapter
breaks while turning the
10-mm box-end wrench
counterclockwise, the adjuster
is seized.

Adjuster must turn in both directions with a hand
wrench.

With the brakes released,
check the running clearance
between the tappet and the
inboard pad.

The gap should be between
0.024 in. (0.6 mm) and 0.047 in. (1.2 mm).

3.2

Caliper only must
be replaced with
malfunctioning adjuster.

3.1

Install and torque the
replacement caliper
per section 4.3.7.

45

NOTES

46

NOTES

47

CONTACTING BENDIX
Bendix Technical Assistance Team
•

For direct personal technical support, call the Bendix Tech Team at 1-800-AIR-BRAKE
(1-800-247-2725), option 2. Representatives are available to assist you Monday through
Thursday, 8:00 am to 6:00 pm and Friday, 8:00 am to 5:00 pm ET, or email the Bendix
Tech Team at: [email protected].

To better serve you, please collect the following information before you call the
Bendix TechTeam, or include this information in your email:
•

Bendix product model number, part number, and configuration.

•

Vehicle make and model.

•

Vehicle configuration. (Number of axles, tire size, etc.)

•

System performance symptoms: When do they occur?

•

What troubleshooting/measurements have been performed?

•

What Bendix service data literature do you have or need?

24/7/365 ACCESS
FULL SERVICE AT YOUR FINGERTIPS

1-800-AIR-BRAKE (1-800-247-2725)
[email protected]

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are solely for identification and cross reference purposes.
The trademarks are the property of their respective companies.
Unless otherwise indicated, the trademarks used in this document, including Bendix, are
United States trademarks owned by, or licensed to, Bendix Commercial Vehicle Systems LLC.

48

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