User's Manual
2
Inspect the
caliper
Push/pull
by hand to check the
caliper movement
[at least 0.75 Inch
(20 mm) with the
pads removed]
Complete this
step on level
ground, with the
wheels chocked
and the parking
brake temporarily
released!
Inspect the
air hoses
(“jounce
lines”).
• Is air trapped in the hose?**
• Do the hose(s) pull or push on the caliper? (It is
important that the hoses permit the lateral motion of
the caliper, the vertical motion of the suspension, and
— for steering axles — the full turn of the wheels.)
• Are there any kinks, restrictions?
• Are the hoses in good condition?
Is
there
2 mm, or less, of
brake pad friction
material?*
Does
the brake
caliper have
restricted movement in
the inboard/outboard
direction?
Are
any of
these conditions
found?
YES
YES
Service the guide pins.
Perform all Section Two inspections.
(Not a Thermal Overload warranty condition.)
Replace the pads (axle set recommended)
after performing all Section Two inspections.
(Not a Thermal Overload warranty condition.)
Service as needed.
Perform all Section Two inspections.
(Not a Thermal Overload warranty condition.)
SECTION TWO: Investigate Other Potential External Causes
• Follow all Safe Maintenance Practices (see nal page.)
Inspect the brake pads.
(New pads have 21 mm of brake pad, plus a 9 mm backing plate.)
**Take full safety precautions during the inspection
for trapped air, to avoid the air hose whipping if air
pressure is found to be trapped. Conditions that
might cause trapped air include kinked lines, or
when an ABS modulator is malfunctioning and
not exhausting service air.
*2 mm of friction material, plus a 9 mm
backing plate, for a total of 11 mm.
NO
NO
YES
NO
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