Chrysler PT Cruiser Service & Repair Manual page 161

PT
ROTOR (Continued)
Fig. 95 Front Brake Rotor Comparison
1 - BRB/BRT BRAKE ROTOR
2 - STANDARD ROTOR THICKNESS
22.91-23.10 MM
3 - PERFORMANCE ROTOR THICKNESS
27.91-28.10 MM
4 - BR4 PERFORMANCE BRAKE ROTOR
5 - INDENTIFYING MACHINED AREA
BRAKING SURFACE INSPECTION
Light braking surface scoring and wear is accept-
able. If heavy scoring or warping is evident, the rotor
must be refaced or replaced. (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/ROTOR - STANDARD
PROCEDURE)
Excessive wear and scoring of the rotor can cause
improper lining contact on the rotor's braking sur-
face. If the ridges on the rotor are not removed before
new brake shoes are installed, improper wear of the
shoes will result.
If a vehicle has not been driven for a period of
time, the rotor's braking surface will rust in the
areas not covered by the brake shoes at that time.
Once the vehicle is driven, noise and chatter from
the disc brakes can result when the brakes are
applied until the rust wears away.
Some discoloration or wear of the rotor surface is
normal and does not require resurfacing when lin-
ings are replaced. If cracks or burned spots are evi-
dent, the rotor must be replaced.
Fig. 96 Rear Brake Rotor Comparison
1 - BRT BRAKE ROTOR
2 - STANDARD ROTOR THICKNESS
8.75-9.25 MM
3 - PERFORMANCE ROTOR THICKNESS
11.75-12.25 MM
4 - BR4 PERFORMANCE BRAKE ROTOR
5 - INDENTIFYING MACHINED AREA
ROTOR MINIMUM THICKNESS
Measure rotor thickness at the center of the brake
shoe contact surface. Replace the rotor if it is worn
below minimum thickness or if machining the rotor
will cause its thickness to fall below specifications.
CAUTION: Do not machine (turn) the rotor if it will
cause the rotor to fall below minimum thickness.
Minimum thickness specifications are cast on the
rotor's unmachined surface (Fig. 97) (or stamped into
the hat section). Limits can also be found in this sec-
tion's specification table. (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTOR
SPECIFICATIONS)
ROTOR THICKNESS VARIATION
Thickness variation in a rotor's braking surface
can result in pedal pulsation, chatter and surge. This
can also be caused by excessive runout in the rotor or
the hub.
BRAKES - BASE 5 - 53
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