bit socket, remove
and discard the two
caliper bolts (39) and
(40). See Figure 67.
By hand, retract both
guide pins slightly,
and then remove
the caliper from the Figure 67 – Remove the
Caliper Bolts
carrier.
The guide pins are now only held by the retaining
rings (58).
4.6.10 Remove the boot
retaining rings (58)
and the guide pins
(39) and (40). Use
a screwdriver to pry
out the inner boots
(9). See Figure 68.
Discard the removed
Figure 68 – Remove the
items.
Retaining Rings, Guide
Pins, and Boots

4.6.14 Turning the bolt at
the top, draw the
brass nut up, bring
the brass bushing
up and out of the
channel. Discard the
bushing.
Figure 71 – Remove the
Long Guide Pin
Caution: Keep the removal tool exactly aligned with
the guide pin channel to permit the bushing
to be removed. See Figure 72.

T12
Bushing (10)
Removed

T13

Bushing
(10)
Installed

4.6.11 Clean the caliper upper and lower surfaces around
the bushings.

T14
Grease the bolt prior to each use

Above: Incorrect
Alignment

Above: Correct
Alignment

Figure 72 – Keep the Correct Alignment
Washer

T12

T13

T14

Figure 69 – B rass Bushing and Short Guide Pin
Bushing Removal Tool for ADB22X and
ADB22X-LT
4.6.12 Prepare to remove the brass bushing used in the
long guide pin side. Assemble the long bolt (T13),
washer, and sleeve (T12) as in Figures 69 and 70.
4.6.13 A p p l y g r e a s e t o
the bolt and – after
inserting through the
guide pin channel –
engage the brass
nut (T14). Always
double-check that
the brass nut is
correctly in place in Figure 70 – Install the
the bushing before Removal Tool
beginning to extract
the bushing.

4.6.15 Prepare to remove
the short guide pin
bushing by locating
the bushing (6) tab,
and – if present –
using a small chisel
(narrower than the
tab) or similar tool,
remove the tab as Figure 73 – Remove
shown in Figure 73, the Tab that Holds the
by striking low on the Bushing in Position
base of the tab.
Remove the tab – if present – with a magnet and
use a clean shop cloth to remove any excess debris.
Note that in some cases, the tab may be in the
opposite (outer) slot in the bore.
Washer

T21

Grease the bolt prior to each use

T20

T14

Figure 75 – Optional Short Guide Pin Bushing Removal
Tool for ADB22X
37

4.6.16 Use the tool combination shown in Figures 74 and
74 (comprising T14, T20 ,T12 or optional T21 per
Figures 69 and 74, and a washer) to remove the
bushing (6). Screw nut (T14) onto the assembly
by hand, then tighten the bolt (T20) using a box
end wrench to draw out the bushing. Discard the
removed bushing, and verify that the bore is clean
by wiping with a shop cloth.
T20

T14

7

Washer
7
T12: ADB22X and ADB22X-LT
T21: Optional for ADB22X

T14

Figure 75 – Sectional View: Short Guide Pin Bushing
Removal

Installation of the Fixed Guide Pin Brass
Bushing

4.6.17 Clean the caliper upper and lower surfaces around
the bushings.
4.6.18 Clamp the carrier in a vise so that the guide channel
is vertically oriented.
Washer

T14

T08

Grease the bolt prior to each use

T16

Figure 76 – Long Guide Pin Bushing Installation and
Dimpling Tool
4.6.19 Place the washer and thread the brass nut (T14) on
to the bolt (T13) followed by the flange (T08). See
Figure 76.
4.6.20 Place a new brass guide bushing (7) on the dimpling
tool (T16) and insert it into the caliper bore.

38

View
“B”

View
“C”

Figure 77 – View “A” and “B”: Draw the Brass
Bushing into Position. View “C”: Lock the Bushing
into Position

6

T13

View
“A”

4.6.21 Check that the flange (T08) is in an upright position
at the top of the caliper recess as you draw the
brass bushing (7) up, by turning the brass nut (T14),
until the dimpling tool bottoms on the caliper. When
it reaches the correct position, the brass bushing
extends out of the guide pin channel 0.039 in.
(1 mm).
4.6.22 With the dimpling tool (T16) in position, tighten the
screw in its base until it contacts the dimpling screw
housing. The movement of this screw forces three
points outwards, leaving indentations in the brass
bushing. See Figure 77, view “C”.
4.6.23 Unscrew the dimpling screw out approximately 0.75
in.es (20 mm). Loosen the brass nut (T14) and
rotate the dimpling tool (T16) 60 degrees. Repeat
the dimpling process by tightening the brass nut
(T14) and then tighten the dimpling screw until it
contacts the dimpling screw housing. Back out the
dimpling screw approximately 0.75 in.es (20 mm).
The brass bushing (7) is now held in position by the
six dimples made by the tool.
4.6.24 Remove the installation tools and check the brass
bushing (7), removing any burrs, being careful not
to leave any metal filings in the bushing. Coat the
inside of the bushing with the white grease included
in the kit.

Installation of the Floating Guide Pin Bushing

4.6.25 To install the bushing (6) into the short guide pin
side, first inspect the bore for corrosion, damage
etc. Clean as necessary.

4.6.26 P l a c e t h e n e w
bushing (6) in
position so that
when drawn into
position, the tab
will align with the
slot in the casting.
With the tab aligned,
place tool (T14) over Figure 78 – Position the
the bushing and tap New Bushing
lightly. To position
the bushing, see
Figure 78.
Grease the bolt prior to each use

Washer

T20

4.6.29 Coat the inside of the bushing (6) with a light coat
of the white grease included in the kit.
4.6.30 Install the two identical inner boots (9) by first
cleaning the area where the inner boots will be
installed and inspect for corrosion. If the sealing
surface of the caliper is damaged, replace the
caliper.
Grease the bolt prior to each use

Washer

T10
T08

T07

Figure 81 – Short Guide Pin Boot Installation Tool

T05

T06

T08

T14

Figure 79 – Short Guide Pin Bushing Installation
Tool
4.6.27 Use the tool combination shown in Figure 79 to draw
the bushing (6) into the caliper. Also see Figure 80,
to see the orientation (with tool T14 at the top). Hand
tighten the nut (T14) into position. Then tighten the
bolt (T20) using a box end wrench or socket to draw
the bushing (6) into the caliper until the bushing (6)
contacts the machined step in the bore. Remove
the tool.

4.6.31 S e e F i g u r e 8 2 .
Place a boot into the
sleeve installation
tool (T07), making
sure that the inner
bellows are arranged
close to the side
walls of the tool and
will not be damaged Figure 82 – Position the
during installation. New Boot in the Sleeve
Also check that the Installation Tool (T07)
outer edge of the
boot rests on the
front edge of the tool.
4.6.32 Using 70 in-lbs (8 N•m) of torque maximum, tighten
bolt (T10) to install the inner boot.
4.6.33 Repeat the installation procedure for the second
inner boot.

T14

6
Bushing Stop
T08
T06
T05
T20

Washer

Figure 80 – Guide Pin Bushing Installation
4.6.28 Using a punch, bend the tab into the groove by
aligning the punch with the upper part of the tab
and tapping the punch with a hammer.

4.6.34 Check that the boots are held securely in place and
that no damage occurred during installation.
4.6.35 See Figure 83. To
install the guide
pins, first lubricate
both guide pins with
the white grease
supplied. Insert the
guide pins into their
respective bores
Figure 83 – Place the
with the grooved end
Retaining Ring onto the
towards the bellows.
Groove in the Guide Pin
Fit the lip in the end of the inner boots (9) into the
groove of the guide pins. Push on each ring (7)
ensuring that the boot (9) is engaged onto the end
of the guide pins (4 or 5).

39

4.6.36 With the caliper resting on a bench, slide the carrier
into place with a slight rocking motion, taking care
that as you do so, the inner boots and guide pins
are seated in their proper place on the carrier.
4.6.37 Identify the two caliper bolts (39) and (40). With the
shorter bolt placed in the floating pin bushing (4), and
the longer bolt placed in the fixed pin bushing (5),
begin to tighten the bolts. With the caliper/carrier
in a vice, continue installing the bolts to a torque of
133 ft-lbs (180 N•m). Finally, tighten each bolt an
additional 90º (ninety degrees).

Installation of the Guide Pin Caps
4.6.38 See Figure 84. Place
Boot
Compressed
the caliper/carrier assembly on a bench
so that the inner
boots are fully compressed, check that
the bores are clean
and dry (e.g. free
Figure 84 – Boots Must
from lubrication).
Be Compressed Fully
During Cap Installation
NOTE: It is important that the inner boots are fully
compressed during this procedure to ensure that
the least amount of air is retained within the guide
pin channel. If too much air is trapped, the bellows
can potentially be damaged during the operation
of the brake. It is also important that the technician
double-check that the retaining rings remain in their
correct position during this procedure.

4.6.39 Clean the two caps, and check that the caliper
surfaces where the caps will be installed are clean
and have no signs of damage.
4.6.40 Select one cap to
install. Using the
correct press-in
tool – the smaller
cap (10) installs
in the long guide
pin side using tool
(T26), and the larger
Figure 85 – Boots Must
cap (68) installs
Be Compressed Fully
in the short guide
During Cap Installation
pin side using tool
(T27) – place the cap
in position, using the
machined channel in
the caliper to assist
in centering the tool.
Use a hammer to tap the cap into position. See
Figure 85. Note that the tool needs to remain
perpendicular to the channel to prevent damage
during installation. Note that, after installation, the
smaller cap (10) extends 0.08 in. (2 mm), and the
larger cap (68) extends 0.61 in. (15.5 mm).
Repeat for the second cap.
4.6.41 Check that the guide pins move freely when the
carrier is moved laterally, and that air is not trapped
within the inner boots, and that the boots (9) and
ring (58) are in the proper position before continuing
with the installation.
4.6.42 Install the caliper/carrier (See Section 4.3).
4.6.43 Install the brake chamber (See Section 4.4).
4.6.44 Install the brake pads (See Section 4.2).

40

4.7 BENDIX® SPLINED DISC® HUB ROTOR
DRIVE HUB

STEER HUB

Intermediate Elements
(Spacers)

Wheel Studs

Intermediate Elements
(Spacers)

Hub
ID Label

Spring Elements
(Retention
Brackets)

Wheel Studs
Hub

ID Label

Spring Elements
(Retention
Brackets)

ABS Tone
Wheel
and Fasteners

Splined Disc Rotor

ABS Tone Wheel
(Press On)

Above: Bendix Splined Disc Rotor on Aluminum Drive Hub
®

Above: Splined Disc Rotor on Aluminum Steer Hub

®

Figure 86 – Splined Disc Rotor Examples - Exploded Views
Bendix® Splined Disc® Hub Rotors are designed to assist
vehicle maintenance by typically allowing the rotor to be
serviced without requiring the entire hub/rotor assembly
be replaced.
Periodic inspection of the Splined Disc attachment
hardware is recommended to ensure optimum braking
performance. Bendix recommends verifying the torque on
the spring element fasteners whenever a brake inspection
is performed.
NOTE: Anytime that the entire hub/rotor assembly is
removed, Bendix recommends that the wheel seal
also be replaced at the same time, USING A HIGHTEMPERATURE SEAL. Follow the wheel seal and/
or vehicle manufacturer's guidelines for full installation
instructions. Adjust the bearings and refill bearing oil to
vehicle manufacturer's specifications.
When replacing a splined disc rotor, Bendix strongly
recommends that the brake pads be replaced (as an
axle set.) Contact 1-800-AIR-BRAKE (1-800-247-2725),
option 2, for the appropriate brake pad kit. Rotor
replacement necessitates the removal of the pads.
CAUTION: Follow all safe maintenance practices,
including those listed on page 2 of this document.
Park the vehicle (by other means than the foundation
brakes) on level ground and chock the wheels. Also
read the vehicle manufacturer's recommendations.
When installing pads, where appropriate, use heavy
duty gloves and always keep fingers away from
potential pin. hazard areas.
Bendix® Air Disc Brakes (ADB) are precision-engineered
braking mechanisms. The “friction couple” braking
characteristics have been carefully optimized and the rotor
design and materials have been matched with special
formulation brake pads for optimal performance, therefore
use only genuine Bendix® brand parts and brake pads.

Bendix air disc brakes are precision-engineered braking
mechanisms. The “friction couple” braking characteristics
have been carefully optimized and the rotor design and
materials have been matched with special formulation
brake pads for optimal performance, therefore use only
genuine Bendix® brand parts and brake pads.

Rotor Replacement

4.7.1 Before removing the brake pads it is strongly
recommended that the air disc brake adjuster
mechanism be checked for correct operation (See
Section 3.1). When replacing brake pads, Bendix
strongly recommends that the pads be replaced as
an axle set.
4.7.2 Refer to the vehicle manufacturer’s recommendations
and release (or cage) spring brakes and remove the
wheel.
4.7.3 Remove the pads (See Section 4.2).
4.7.4 Remove the air disc brake (See Section 4.3).
4.7.5 Remove the hub rotor assembly.
NOTE: Follow the vehicle manufacturer's guidelines for
removal of the wheel hub and rotor assembly from the
vehicle in lieu of these instructions, where available.
CAUTION: Be sure to secure both the rotor and hub
before removing the retention clips.
U-Shape rotor removal Caution: The fasteners
typically use a thread lock compound. Secure
the hub-rotor prior to removal. Remove and discard
the fasteners attaching the rotor to the axle. Discard
the rotor.
4.7.6 Remove and discard the ten spring elements.
4.7.7 On drive axles, the ABS tone ring must also be
removed. See Figure 86. Retain for reinstallation.
41

4.7.8 Use suitable hand tools to remove the intermediate
elements (spacers). Remove all the right-hand
intermediate elements (spacers) of each set first
and then the rotor can be turned slightly to release
the remaining intermediate elements (spacers).
In all cases, take care not to damage the hub and
its teeth. Remove and discard the intermediate
elements (spacers) and retention clips attaching
the rotor. Discard the rotor.
4.7.9 Following industry standards, clean and inspect the
hub before installing the rotor. Look for corrosion
and/or damage to the hub and inspect the wheel
speed tone ring. Where necessary, consult the hub
manufacturer's guidelines for more details.