Compare the new pads with the old ones to ensure
they are correct. Be sure to note whether the mounting
surfaces (metal shoe) portion is correct, and the linings are
not too thick to prevent the caliper from fitting over the
rotor. After ensuring the pads are correct, install any clips
and anti-squeal insulators on the new pads. If the vehicle
has a separate pad wear sensor, install it in the proper
position, Figure 13-13. If desired, place anti-squeal
compound on the pad shoes where they contact the
caliper. See Figure 13-14.
Place high temperature lubricant on the parts of the
caliper that move in relation to the spindle assembly.
Typical lubrication points would be the sliding surfaces of
the caliper and spindle, guide pins, sleeves and bushings,
and any related moving parts. Do not use motor oil, wheel
bearing grease, or chassis lubricant. The high temperatures
of the brake system will cause it to burn off almost imme-
diately, leaving a sticky residue which will interfere with
brake operation.
Caliper Reinstallation
Caliper reinstallation is relatively simple, but must be
done correctly if the brakes are to operate properly. Install
the rotor if it was removed. Before reinstalling the caliper,
check the spindle assembly, splash shield, and other
related parts for damage. Place high temperature lube on
any sliding surfaces of the spindle or adapter bracket.
Place the caliper over the rotor, Figure 13-15. If the
caliper does not slide easily over the rotor, do not force it
into place. Remove it and check to see if the piston is fully
retracted and the pads are correct. Some vehicles require
that one end of the caliper be installed first. On other vehi-
cles, the caliper must enter straight into the mounting
bracket. After the caliper is in position, install the attaching
hardware and the brake hose if necessary.
After the fasteners are tight, ensure the rotor can turn
freely with the caliper installed. While turning the rotor, lis-
ten for scraping noises that indicate the caliper or another
stationary part is contacting the rotor. Bleed the brakes if
necessary, then reinstall the tire and rim.
Staking the Brake Pads
Some brake caliper designs require the technician to
pinch a portion of the outer pad shoe against the caliper.
This is referred to as clinching or staking the brake pads.
Staking must be performed to prevent the outer pad from
moving. This procedure is done using a large pair of
adjustable pliers (channel lock) or a hammer. Have an
assistant pump the brake pedal to bring the pads against
the rotor. Then, while the assistant presses the brake pedal,
stake the outer pads to the caliper, Figure 13-16.
Chapter 13 Disc Brake Service 215
Figure 13-13. Installing one type of outboard brake shoe and
lining. Note the retaining clip and audible wear sensor position.
Audible wear sensor Outboard
brake pad brake pad
Figure 13-14. Two different styles of brake pad shoes showing
the correct placement of anti-squeal compound. Do not allow
this compound to touch the friction material. (Bendix)
Note: Some technicians prefer to slightly
bevel (grind) the edges of the pads to
reduce the likelihood of brake squealing.
Some newer pads come with beveled edges from the
Caution: Do not allow non-graphite anti-
squeal compounds or lubricants to touch
the pad friction surfaces or rotor.
Note: If the calipers were removed from the
vehicle, be careful not to switch calipers
between the left and right sides of the
vehicle. On many vehicles, reversing the calipers will
place the bleeder screws in a position that makes it
impossible to completely remove all air from the
Caution: Start all fasteners by hand before
using a hand or air tool to tighten.
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