12
FIGURE 21 - MAJOR
PAD DAMAGE IS
NOT ACCEPTABLE
Section
Damaged or
Missing
FIGURE 20 - MINOR
PAD DAMAGE IS
ACCEPTABLE
Small Amount of
Brake Material
Chipped from
Edge
INSPECTIONS
Follow all standard safety procedures including, but not
limited to, those on page 2 of this service manual.
BRAKE PADS AND ROTORS
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.
CAUTION: When replacing brake pads, Bendix
strongly recommends using only replacement pads
and replacement rotors approved by the OEM. Use
of non-approved rotors or non-approved replacement
disc pads can cause excess wear to brake components,
and can increase the risks of rotor cracking, etc. Note
that two thicknesses of backing plate are generally
available, so to maintain the vehicle within spec's
only use brake pads with the type of backing plate
and lining material originally supplied by the vehicle
manufacturer. See the manual supplied with the
vehicle for further information.
INSPECT BRAKE PADS
Regular inspection of the brake pads (even for vehicles
that use a wear indicator) is an important part of vehicle
maintenance.
See Figure 16. If the thickness of the friction material (M2)
is less than 0.079 in. (2 mm) the pads must be replaced.
Bendix
®
ADB 22X
™
, ADB 225
™
, SN6
™
, SN7
™
(and some
SK7
™
) air disc brakes use 0.35 in. (9 mm) backing plates,
so P2 (the combined pad and backing plate thickness)
must be a minimum of 0.43 in. (11 mm).
Note that for some Bendix
®
SK7
™
air disc brakes, a 0.28 in.
(7 mm) backing plate is used, so P2 (the combined pad
and backing plate thickness) must be a minimum of 0.35 in.
(9 mm).
If the pad thickness is within the acceptable range, inspect
the pad surface. Minor damage at the edges is permitted
(see Figure 20), but replace the pads if major damage on
the surface of the pad is found (see Figure 21).
When replacing brake pads, Bendix strongly recommends
that all the brake pads on an axle be replaced at one time.
See pages 18-19 for the pad replacement procedure. Also
see the vehicle manual recommendations.
FIGURE 19 - PAD AND ROTOR DIMENSIONS
Bendix
®
ADB 22X
™
,
ADB 225
™
, SN6
™
,
and some SK7
™
Air Disc Brake Pads
B (Backing
P2 (Pad min.
plate thickness) thickness)
0.35 in.
0.43 in.
(9 mm.)
(11 mm.)
0.28 in.
0.35 in.
(7 mm.)
(9 mm.)
SK7
™
Air Disc Brake
Pads with 0.28 in.
(7 mm) backing plate
