CHEVROLET CORVETTE C8 2021 Owners Manual

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 9/22/20
180 Driving and Operating
Be sure to follow all service procedures
before driving the vehicle at track events or
competitively.
{Warning
Prior to each track event and again
before returning to public roads, tighten
the wheel nuts with a torque wrench to
the proper torque specification. Wheel
nuts that are improperly or incorrectly
tightened can cause the wheels to
become loose or come off, resulting in a
crash. SeeCapacities and Specifications
0 305 for wheel nut torque specifications.
If equipped, the front license plate bracket
should be removed and replaced with the
aero cover for track use.
Engine Sound Management Setting Caution
Do not place the vehicle in Engine Sound
Management–Stealth mode. Damage
could result to exhaust valve actuators.
Engine Oil
Caution
If the vehicle is used for track events and
competitive driving, the engine may use
more oil than it would with normal use.
Low oil levels can damage the engine.
Check the oil level often and maintain
the proper level. See Engine Oil0238.
Check the oil level often during track events
and competitive driving. See “Checking the
Engine Oil" in Engine Oil0238.
Engine Cooling
If reduced performance is experienced during
track events or competitive driving, turning
off the A/C will help to improve engine
performance.
Maintain a mixture of 40% DEX-COOL
coolant and 60% clean, drinkable water to
optimize engine performance.
Fuel
Unleaded gasoline, rated at 93 octane or
higher, is required.
Caution
Some high octane fuels contain additives
and compounds that may damage the
vehicle and void the vehicle warranty. See
Prohibited Fuels 0226.
Dual Clutch Transmission Fluid
The transmission fluid and external filter
should be changed after every 24 hours of
track usage. If prompted by the transmission
fluid life monitor that remaining fluid life is
low, the fluid and external filter should be
changed as soon as possible.
Add an additional 2 L (2 qt) of DCT
transmission fluid prior to track usage. It is
not required to remove the additional 2 L
(2 qt) of DCT fluid.
Any transmission level set or change should
be performed at your dealer.
Brakes
Battery Disconnect
Disconnect the battery before servicing the
hydraulic brake system. It is critical to
disconnect the battery before bleeding the
system, replacing the pads, or any other
work. The battery must be disconnected to

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 9/22/20
Driving and Operating 181
prevent the brake master cylinder from
pressurizing the hydraulic system during its
automated self diagnostic tests that can
possibly occur when a door is opened or the
remote key is present.
{Caution
To avoid personal injury and/or vehicle
damage, always disconnect the battery
before performing service work on the
hydraulic brake system. Bleeding the
brake system with the battery connected
can lead to excessive pressurization of
the system during automatic diagnostic
tests or diagnosis of a leak or air in the
braking system. A Diagnostic Trouble
Code (DTC) may set and vehicle speed
may be limited.
Brake Fluid
Replace existing brake fluid with a qualified
high performance DOT 4 brake fluid from a
sealed container. Brake fluid with a dry
boiling point >310 °C (590 °F) is qualified.
If high performance brake fluid is used,
replace it with GM approved brake fluid
before driving on public roads. If high
performance brake fluid is in the vehicle and
the age of the brake fluid is over a month old or unknown, replace the brake fluid
before track events and competitive driving.
Do not use silicone or DOT-5 brake fluids.
Check the fluid level before each competitive
driving event.
Brake System Flushing & Bleeding
The J55 brake system requires specific
processes for bleeding and fluid flushing.
These can be found in the service manual.
Properly bleeding the brake system is
required for proper operation of the
hydraulic brake system.
Brake Leak Detection
The hydraulic braking system has advanced
diagnostic capability to help detect hydraulic
leaks, trapped air, and other performance
issues. These diagnostics are active when
the hydraulic system is powered. In order to
avoid inadvertently setting a leak Diagnostic
Trouble Code (DTC), disconnect the battery
before servicing the brake system.
If the vehicle sets a DTC related to a brake
system leak, the Brake System Warning
Light will come on and vehicle speed may
be limited to 100 kph (62 mph). Any time a
leak DTC is set, the vehicle should be
inspected carefully for evidence of a leak
and should be repaired immediately. See
your dealer.
Brake Fade Warning Assist
The Brake Fade Warning Assist system
monitors the performance of the brake
system. If the system detects brake fade,
or if the brake fluid is near the boiling point,
the driver will be alerted.
The Brake Fade Warning Assist system is
designed for use with the factory-installed
brake pads or GM-approved replacement
pads. If the brake pads on the vehicle need
to be replaced, use GM-approved brake pads.
If this is not done, the brake fade warning
system may not function properly.
Stage 1 :
The Driver Information Center (DIC)
displays a “Reduce Braking to Avoid
Overheating” message and brake pedal
effort and travel is increased. When the
message displays, the driver should decrease
brake pedal pressure.
Stage 2 : The Driver Information Center
(DIC) displays a “Brakes Overheated Service
Now” message that the brake fluid
temperature is excessive and is about to
boil. The system increases brake pedal effort
and travel, and will also limit vehicle speed.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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182 Driving and Operating
The driver should immediately start a cool
down lap if on the track. If this message
displays, take the vehicle to be serviced at
your dealer.
Brake Burnishing
New brake pads must be burnished before
racing or other competitive driving.
Caution
Performing the brake burnish procedure
on a base brake system can result in
brake damage.
Caution
The new vehicle break-in period should be
completed before performing the brake
burnish procedure, otherwise damage
may occur to the powertrain/engine. See
New Vehicle Break-In0190.
Caution
Brake pedal fade will occur during any
track burnish procedure and can cause
brake pedal travel and force to increase.
This could extend stopping distance until
the brakes are fully burnished. When this procedure is performed as
instructed, it will not damage the brakes.
The brake pads will smoke and produce an
odor. The braking force and pedal travel
may increase. After the procedure, the brake
pads may appear white at the rotor contact.
Perform this procedure only on dry
pavement, in a safe manner, and in
compliance with all local and state
ordinances/laws regarding motor vehicle
operation.
Brake Burnishing Procedure
This brake burnish procedure should only be
run on vehicles with the J55 Z51 factory
equipped brake system.
1. Apply the brakes 25 times starting at 100 km/h (60 mph) to 50 km/h (30 mph)
while decelerating at 0.4 g. This is a
medium brake application. Drive for at
least 1 km (0.6 mi) between applying the
brakes. This first step may be skipped if
there are more than 320 km (200 mi) on
the brake pads.
2. Apply the brakes 25 times starting at 100 km/h (60 mph) to 25 km/h (15 mph)
while decelerating at 0.8 g. This is a hard
brake application without activating the
Antilock Brake System (ABS). Drive for at least 1 km (0.6 mi) between applications.
Depending on conditions, some increase
in brake pedal travel and brake pedal
force may be experienced.
3. Cool down: Drive at 100 km/h (60 mph) for approximately 15 km (10 mi) without
using the brakes.
4. Apply the brakes 25 times from 100 km/h (60 mph) to 50 km/h (30 mph)
while decelerating at 0.4 g. This is a
medium brake application. Drive for at
least 1 km (0.6 mi) between applications.
As with all high performance brake systems,
some amount of brake squeal is normal.
Alternative Closed Course Brake Burnishing
Procedure
This brake burnish procedure should only be
run on vehicles with the J55 Z51 factory
equipped brake system.
This procedure should only be run on a
track and only on dry pavement. Brake
pedal fade will occur during this track
burnish procedure and can cause brake pedal
travel and force to increase. This could
extend stopping distance until the brakes
are fully burnished.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 183
1. Start track lapping at lower speeds andlower braking efforts for three minutes
of driving. Allow for increased braking
distances due to reduced brake output.
2. After Step 1, increase speed and braking effort for the next six minutes of
lapping, gradually ending up at 90%
effort. Continue to allow for increased
braking distance due to reduced brake
output.
3. Cool the brakes by lapping with minimal light braking for six minutes.
Brake Cooling Kit
Prior to any track event, high speed driving
event, or competitive driving, the following
should be completed:
.Ensure all brake cooling parts are
correctly and securely installed.
.Install the rear lower control arm cooling
ducts per the instructions below also
included with the kit. After any track
event or competitive driving, remove the
rear lower control arm cooling ducts.
These parts are for track use only.
Removing the ducts helps prevent debris
from being channeled into the rear brakes
during regular use of the vehicle.
.Inspect for and remove any blockage in
the ducts.
.Inspect and replace any duct that has
damage.
Passenger Side Front Shown, Driver Side Front Similar
1. Front Brake Cooling Duct
2. Front Lower Control Arm Deflector
Passenger Side Rear Shown, Driver Side Rear Similar
3. Rear Knuckle Mounted Cooling Duct
4. Rear Lower Control Arm Cooling Duct
Shock Spring Seat Adjustment
The front shocks, on vehicles without
hydraulic front lift and rear shocks, have
threaded spring seats that allow adjustment
of the preload on the coil springs. The
vehicle corner weights can be adjusted for
track use. If the vehicle trim height is
modified, it should be returned to normal
trim height before street use.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 9/22/20
184 Driving and Operating
The spring seat can be adjusted
approximately 20 mm (0.8 in) up or down
from the nominal position. Each complete
turn of the spring seat will change the
vehicle height approximately 1.5 mm
(0.06 in). When adjusting the seat to the
upper limit, lift the dust boot and ensure
the seat does not thread off the center
support tube (stop adjustment when threads
no longer visible). When adjusting the seat
to the lower limit, leave approximately
10 mm (0.4 in) of thread visible for the
lower lock nut to have full thread
engagement.
The following procedure can be complex and
should only be performed by trained
personnel. See your dealer.
To adjust the lower spring seat:1. Raise the vehicle so the tires are completely off the ground.
Front Shown, Rear Similar
2. Loosen the lower spring seat lock nut (2).
3. Thread the lower spring seat lock nut (2) downward off of the threads to its
resting location on the shoulder of the
center support tube.
4. While holding the center support tube holes, turn the spring seat (1) upward to
increase spring preload, or downward to
decrease spring preload.
5. Thread the lower lock nut (2) back on to the center support tube and torque it
against the spring seat (1) to 25 Y
(18.4 lb ft).
Load Limit
Limit vehicle load to the driver only, with no
other cargo. Inflate the front tires to 159 kPa
(23 psi) and the rear tires to 165 kPa (24 psi).
Drive at a maximum speed of 296 km/h
(184 mph).
Road Course target hot pressures of
220–240 kPa (32–35 psi). Value will vary
based on driving style, track, temperature,
and weather conditions.
Wheel Alignment
Caution
Using these wheel alignment settings
may cause excessive tire wear. Only use
these wheel alignment settings for racing
or competitive driving. Excessive tire wear
is not covered under the vehicle
warranty.

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Driving and Operating 185
Caution
Do not use power tools when removing
or installing the fasteners. Damage to the
threads may occur. Use hand tools only,
and do not overtighten. Hand start the
fasteners to ensure that the threads do
not bind or cross thread.
The racing and competitive driving wheel
alignment settings should be set as
described here.
To achieve the track alignment specified
settings: 1. The upper control arm to body washers on all four corners will need to be
moved from between the body and the
control arm and relocated between the
head of the bolt and the control arm.
2. Adjust the lower control arm cam bolt position to achieve the following
specifications.
Front (per corner)
.Caster: +8.0 degrees
.Camber: -3.0 degrees
.Toe (total): 0.1 degrees toe in Rear (per corner)
.Caster: 0 degrees
.Camber: -2.5 degrees
.Toe (total): 0.1 degrees toe in
.Thrust Angle: 0 degrees
After track use, reinstall washers between
the body and the control arms. Reset to
factory alignment settings. See your dealer.
Driving on Wet Roads
Rain and wet roads can reduce vehicle
traction and affect your ability to stop and
accelerate. Always drive slower in these
types of driving conditions and avoid driving
through large puddles and deep-standing or
flowing water.
{Warning
Wet brakes can cause crashes. They
might not work as well in a quick stop
and could cause pulling to one side. You
could lose control of the vehicle.
After driving through a large puddle of
water or a car/vehicle wash, lightly apply
the brake pedal until the brakes work
normally. (Continued)
Warning (Continued)
Flowing or rushing water creates strong
forces. Driving through flowing water
could cause the vehicle to be carried
away. If this happens, you and other
vehicle occupants could drown. Do not
ignore police warnings and be very
cautious about trying to drive through
flowing water.
Caution
Driving through deep puddles or standing
water can cause water to come in
through the engine air intake and
damage the engine. If deep puddles or
standing water cannot be avoided,
proceed with caution and do not exceed
8 km/h (5 mph). Do not drive through
water that may come close to or cover
the vehicle’s underbody.
Hydroplaning
Hydroplaning is dangerous. Water can build
up under the vehicle's tires so they actually
ride on the water. This can happen if the

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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186 Driving and Operating
road is wet enough and you are going fast
enough. When the vehicle is hydroplaning, it
has little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to slow
down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather
driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping equipment in
good shape.
.Keep the windshield washer fluid reservoir
filled.
.Have good tires with proper tread depth.
SeeTires 0261.
.Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through mountains
is different than driving on flat or rolling
terrain. Tips include:
.When driving downhill in D (Drive), the
vehicle may automatically downshift to
assist with speed control.
.A lower gear may also be selected to
provide further speed control.
{Warning
Using the brakes to slow the vehicle on a
long downhill slope can cause brake
overheating, can reduce brake
performance, and could result in a loss of
braking. Shift the transmission to a lower
gear to let the engine assist the brakes
on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or with
the ignition off is dangerous. This can
cause overheating of the brakes and loss
of steering assist. Always have the engine
running and the vehicle in gear.
.Drive at speeds that keep the vehicle in
its own lane. Do not swing wide or cross
the center line.
.Be alert on top of hills; something could
be in your lane (e.g., stalled car, crash).
.Pay attention to special road signs (e.g.,
falling rocks area, winding roads, long
grades, passing or no-passing zones) and
take appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and the road
creates less traction or grip, so drive
carefully. Wet ice can occur at about 0 °C
(32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.Accelerate gently. Accelerating too quickly
causes the wheels to spin and makes the
surface under the tires slick.
.Turn on Traction Control. See Traction
Control/Electronic Stability Control 0205.
.The Antilock Brake System (ABS) improves
vehicle stability during hard stops, but
the brakes should be applied sooner than
when on dry pavement. See Antilock
Brake System (ABS) 0203.
.Allow greater following distance and
watch for slippery spots. Icy patches can
occur on otherwise clear roads in shaded
areas. The surface of a curve or an
overpass can remain icy when the
surrounding roads are clear. Avoid sudden
steering maneuvers and braking while
on ice.

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Driving and Operating 187
.Turn off cruise control.
.Turn on Weather Mode. SeeDriver Mode
Control 0207.
Blizzard Conditions
Stop the vehicle in a safe place and signal
for help. Stay with the vehicle unless there
is help nearby. If possible, use Roadside
Assistance. See Roadside Assistance Program
0 311. To get help and keep everyone in the
vehicle safe:
.Turn on the hazard warning flashers.
.Tie a red cloth to an outside mirror.
{Warning
Snow can trap engine exhaust under the
vehicle. This may cause exhaust gases to
get inside. Engine exhaust contains
carbon monoxide (CO), which cannot be
seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in snow:
.Clear snow from the base of the
vehicle, especially any blocking the
exhaust pipe.
(Continued)
Warning (Continued)
.Open a window about 5 cm (2 in) on
the vehicle side that is away from the
wind, to bring in fresh air.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to
circulate the air inside the vehicle and
set the fan speed to the highest
setting. See“Climate Control Systems.”
For more information about CO, see
Engine Exhaust 0196.
To save fuel, run the engine for short
periods to warm the vehicle and then shut
the engine off and partially close the
window. Moving about to keep warm also
helps.
If it takes time for help to arrive, when
running the engine, push the accelerator
pedal slightly so the engine runs faster than
the idle speed. This keeps the battery
charged to restart the vehicle and to signal
for help with the headlamps. Do this as
little as possible, to save fuel.
If the Vehicle Is Stuck
Slowly and cautiously spin the wheels to
free the vehicle when stuck in sand, mud,
ice, or snow.
If stuck too severely for the traction system
to free the vehicle, turn the traction system
off and use the rocking method. See
Traction Control/Electronic Stability Control
0 205.
{Warning
If the vehicle's tires spin at high speed,
they can explode, and you or others
could be injured. The vehicle can
overheat, causing an engine compartment
fire or other damage. Spin the wheels as
little as possible and avoid going above
56 km/h (35 mph).
Rocking the Vehicle to Get it Out
Turn the steering wheel left and right to
clear the area around the front wheels. Turn
off any traction system. Shift back and forth
between R (Reverse) and a low forward gear,
spinning the wheels as little as possible. To
prevent transmission wear, wait until the
wheels stop spinning before shifting gears.
Release the accelerator pedal while shifting,

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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188 Driving and Operating
and press lightly on the accelerator pedal
when the transmission is in gear. Slowly
spinning the wheels in the forward and
reverse directions causes a rocking motion
that could free the vehicle. If that does not
get the vehicle out after a few tries, it may
need to be towed out. If the vehicle does
need to be towed out, seeTowing the
Vehicle 0281.
Vehicle Load Limits
It is very important to know how much
weight the vehicle can carry. This
weight is called the vehicle capacity
weight and includes the weight of all
occupants, cargo, and all
nonfactory-installed options. Two labels
on the vehicle may show how much
weight it may properly carry: the Tire
and Loading Information label and the
Certification label.
{Warning
Do not load the vehicle any heavier
than the Gross Vehicle Weight Rating
(GVWR), or either the maximum
front or rear Gross Axle Weight
(Continued)
Warning (Continued)
Rating (GAWR). This can cause
systems to break and change the
way the vehicle handles. This could
cause loss of control and a crash.
Overloading can also reduce stopping
performance, damage the tires, and
shorten the life of the vehicle.
Tire and Loading Information Label
Label Example
A vehicle-specific Tire and Loading
Information label is attached to the
center pillar (B-pillar). This label shows the number of occupant seating
positions (1), and the maximum vehicle
capacity weight (2) in kilograms and
pounds.
The Tire and Loading Information label
also shows the size of the original
equipment tires (3) and the
recommended cold tire inflation
pressures (4). For more information on
tires and inflation see
Tires0261 and
Tire Pressure 0267.
There is also important loading
information on the vehicle Certification
label. It may show the Gross Vehicle
Weight Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for the
front and rear axle. See “Certification
Label” later in this section.
Steps for Determining Correct Load Limit–
1.
Locate the statement "The combined
weight of occupants and cargo
should never exceed XXX kg or
XXX lbs." on your vehicle’s placard.
2.Determine the combined weight of
the driver and passengers that will
be riding in your vehicle.

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Driving and Operating 189
3.Subtract the combined weight of the
driver and passengers from XXX kg
or XXX lbs.
4.The resulting figure equals the
available amount of cargo and
luggage load capacity. For example,
if the "XXX" amount equals 1400 lbs.
and there will be five 150 lb
passengers in your vehicle, the
amount of available cargo and
luggage load capacity is 650 lbs.
(1400-750 (5 x 150) = 650 lbs.)
5.Determine the combined weight of
luggage and cargo being loaded on
the vehicle. That weight may not
safely exceed the available cargo and
luggage load capacity calculated in
Step 4.
6.If your vehicle will be towing a
trailer, load from your trailer will be
transferred to your vehicle. Consult
this manual to determine how this
reduces the available cargo and
luggage load capacity of your
vehicle.”This vehicle is neither designed nor
intended to tow a trailer.
Example 1
1. Vehicle Capacity Weight for Example 1
= 181 kg (400 lbs)
2. Subtract Occupant Weight @ 68 kg (150 lbs) × 1 = 68 kg (150 lbs)
3. Available Occupant and Cargo Weight = 113 kg (250 lbs)
Example 2
1. Vehicle Capacity Weight for Example 2= 181 kg (400 lbs)
2. Subtract Occupant Weight @ 68 kg (150 lbs) × 2 = 136 kg (300 lbs)
3. Available Cargo Weight = 45 kg (100 lbs)