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The ZR1 also has an electronic brake pad wear sensor
system. When pads are worn, the CHANGE BRAKE
PADS message displays in the Driver Information Center.
SeeDIC Warnings and Messages on page 3-54.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly applied.
This does not mean something is wrong with the brakes.
Brake linings should always be replaced as complete
axle sets.
Brake Rotor Wear
ZR1 models have ceramic brake rotors. Rotors should
be visually inspected whenever the brake pads are
replaced. Rotors also need to be weighed before brake
pads are replaced to con rm that the rotor mass is
greater than the wear-out mass printed on the rotor.
The rotor can be reused if the weight of the rotor is above
the mass limit. Rotor inspection and weighing methods
can be found in the service manual. SeeService
Publications Ordering Information on page 7-15.
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Brake Rotor Protector
{CAUTION:
Ceramic rotors will be very hot after operation and
touching them may cause burns. Be sure brake
system is completely cool prior to installation of
protector, or coming in contact with them.
Notice:Rotors may be chipped if hard contact is
made with the wheel during wheel installation or
removal. Always use the rotor protectors. Be sure to
carefully follow wheel removal and installation
instructions.
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A rotor protector should always be installed before any
wheel removal. The protector can be installed by feeding
it through the wheel spokes and slipping it over the outer
edge of the rotor. Leave the protector in place, over the
rotor edge, until the wheel is re-installed. Rotor protectors
are available through your dealer/retailer.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase
in pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the disc brakes automatically adjust
for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced — for
example, when the brake linings wear down and new
ones are installed — be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance expected can change in
many other ways if the wrong replacement brake parts
are installed.
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Tightening Wheel Lug Nuts
{CAUTION:
Never use oil or grease on studs or the threads
of the wheel nuts. If you do, the wheel nuts might
come loose and the wheel could fall off, causing
a crash.
{CAUTION:
Incorrect wheel nuts or improperly tightened wheel
nuts can cause the wheel to become loose and
even come off. This could lead to a crash. Be sure
to use the correct wheel nuts. If you have to replace
them, be sure to get new GM original equipment
wheel nuts.Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque speci cation.
Tighten the wheel lug nuts
rmly in a crisscross
sequence as shown.
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Engine cooling system service (or every
ve years, whichever occurs rst).
An Emission Control Service.
See footnote (i).•
ZR1 Only: Intercooler system service
(or every ve years, whichever occurs
rst).See footnote (n).•
Inspect engine accessory drive belt.
An Emission Control Service.
See footnote (l).•
Change clutch hydraulic uid at a
regular maintenance service every
two years.See footnote (m).
Maintenance Footnotes
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc. Inspect disc
brake pads for wear and rotors for surface condition.
Inspect other brake parts, including calipers, parking
brake, etc.(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts or
signs of wear. Inspect power steering lines and hoses
for proper hook-up, binding, leaks, cracks, chafing,
etc. For ZO6 and ZR1 models and vehicles with the Z51
performance package, lubricate the outer ends of
both rear toe-links.
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