2021 CHEVROLET SUBURBAN air condition

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
318 Vehicle Care
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. SeeRecommended Fluids and
Lubricants 0395.
Change the fluid and filter at the scheduled
maintenance intervals listed in Maintenance
Schedule 0386. Be sure to use the
transmission fluid listed in Recommended
Fluids and Lubricants 0395.
Engine Air Filter Life System
If equipped, this feature provides the engine
air filter’s remaining life and best timing for
a change. The timing to change an engine
air filter depends on driving and
environmental conditions.
When to Change the Engine Air Filter
When the Driver Information Center (DIC)
displays a message to replace the engine air
filter at the next oil change, follow this
timing. When the DIC displays a message to replace
the engine air filter soon, replace the engine
air filter at the earliest convenience.
The system must be reset after the engine
air filter is changed.
If the DIC displays a message to check the
engine air filter system, see your dealer.
How to Reset the Engine Air Filter Life
System
To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information Center (DIC) 0119.
3. Press the thumbwheel on the steering wheel to move to the Reset/Disable
display area. Select Reset then press the
thumbwheel for several seconds.
4. Press the thumbwheel to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is on the driver
side of the engine compartment. See Engine
Compartment Overview 0312.
When to Inspect the Engine Air Cleaner/
Filter
If the vehicle is not equipped with the
engine air filter life system see Maintenance
Schedule 0386 for intervals on inspecting
and replacing the engine air cleaner filter.
How to Inspect/Replace the Engine Air
Cleaner/Filter
Do not start the engine or have the engine
running with the engine air cleaner/filter
housing open. Before removing the engine
air cleaner/filter, make sure that the engine
air cleaner/filter housing and nearby
components are free of dirt and debris. Do
not clean the engine air cleaner/filter or
components with water or compressed air.
To inspect or replace the engine air cleaner/
filter:

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 323
Check to see if the engine cooling fan(s) are
running. If the engine is overheating, the
fans should be running. If they are not, do
not continue to run the engine. Have the
vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If Steam is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam is Coming from the Engine
Compartment
The ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious problem.
If there is an engine overheat warning, but
no steam is seen or heard, the problem may
not be too serious. Sometimes the engine
can get a little too hot when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer; seeTrailer Towing0284.
If the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE
message appears with no sign of steam, try
this for a minute or so: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral), and
let the engine idle. If the engine coolant temperature gauge is
no longer in the overheat zone or an
overheat warning no longer displays, the
vehicle can be driven. Continue to drive the
vehicle slowly for about 10 minutes. Keep a
safe vehicle distance from the vehicle in
front. If the warning does not come back on,
continue to drive normally and have the
cooling system checked for proper fill and
function.
If the warning continues, pull over, stop, and
park the vehicle right away.
If there is still no sign of steam and the
vehicle is equipped with an engine driven
cooling fan, push down the accelerator until
the engine speed is about twice as fast as
normal idle speed for at least five minutes
while the vehicle is parked. If the warning is
still there, turn off the engine and get
everyone out of the vehicle until it
cools down.
If there is no sign of steam, idle the engine
for five minutes while parked. If the warning
is still displayed, turn off the engine until it
cools down.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
324 Vehicle Care
Engine Fan
If the vehicle has electric cooling fans, the
fans may be heard spinning at low speed
during most everyday driving. The fans may
turn off if no cooling is required. Under
heavy vehicle loading, trailer towing, high
outside temperatures, or operation of the air
conditioning system, the fans may change
to high speed and an increase in fan noise
may be heard. This is normal and indicates
that the cooling system is functioning
properly. The fans will change to low speed
when additional cooling is no longer
required.
The electric engine cooling fans may run
after the engine has been turned. off. This is
normal and no service is required.
Washer Fluid
What to Use
When windshield washer fluid needs to be
added, be sure to read the manufacturer's
instructions before use. Use a fluid that has
sufficient protection against freezing in an
area where the temperature may fall below
freezing.
Adding Washer Fluid
The vehicle has a low washer fluid message
on the DIC that comes on when the washer
fluid is low. The message is displayed for
15 seconds at the start of each ignition cycle.
When the WASHER FLUID LOW ADD FLUID
message displays, washer fluid will need to
be added to the windshield washer fluid
reservoir.
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview0312 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
(Continued)
Caution (Continued)
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
.Do not mix water with ready-to-use
washer fluid. Water can cause the
solution to freeze and damage the
washer fluid tank and other parts of
the washer system.
.When using concentrated washer fluid,
follow the manufacturer instructions
for adding water.
.Fill the washer fluid tank only
three-quarters full when it is very cold.
This allows for fluid expansion if
freezing occurs, which could damage
the tank if it is completely full.
Brakes
Disc brake pads have built-in wear indicators
that make a high-pitched warning sound
when the brake pads are worn and new
pads are needed. The sound can come and
go or be heard all the time the vehicle is
moving, except when applying the brake
pedal firmly.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 325
{Warning
The brake wear warning sound means
that soon the brakes will not work well.
That could lead to a crash. When the
brake wear warning sound is heard, have
the vehicle serviced.
Caution
Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can
cause a brake squeal when the brakes are
first applied or lightly applied. This does not
mean something is wrong with the brakes.
Properly torqued wheel nuts are necessary
to help prevent brake pulsation. When tires
are rotated, inspect brake pads for wear and
evenly tighten wheel nuts in the proper
sequence to torque specifications in
Capacities and Specifications 0398.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer 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 may be required.
Replacing Brake System Parts
Always replace brake system parts with
new, approved replacement parts. If this is
not done, the brakes may not work
properly. The braking performance expected
can change in many other ways if the
wrong replacement brake parts are installed
or parts are improperly installed.
Brake Pad Life System
When to Change Brake Pads
This vehicle has a system that estimates the
remaining life of the front and rear brake
pads. Brake pad life is displayed in the
Driver Information Center (DIC), along with
a percentage for each axle. The system must
be reset every time the brake pads are
changed.
When the system has determined that the
brake pads need to be replaced, a message
will display, which may include mileage
remaining. Brake pads should always be replaced as
complete axle sets.
How to Reset the Brake Pad Life System
The system will automatically detect when
significantly worn brake pads are replaced.
When the ignition is turned on after new
pads and wear sensors are installed, a
message will display. Follow the prompts to
reset the system.
The brake pad life system can also be
manually reset:
1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC) 0119.
2. Press the thumbwheel or the trip odometer reset stem if the vehicle does
not have DIC buttons. Select front or rear
pads as appropriate.
3. Select YES on the confirmation message, or press the trip odometer reset stem on
a base level DIC. Repeat for pads on the
other axle if they were also replaced.
How to Disable the Brake Pad Life
System
The brake pad life system can be turned off.
This may be necessary if aftermarket brake
pads without wear sensors are installed.
When the system is turned off, the front

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
344 Vehicle Care
(8) Temporary Use Only:Only use a
temporary spare tire until the road tire
is repaired and replaced. This spare tire
should not be driven on over 112 km/h
(70 mph), or 88 km/h (55 mph) when
pulling a trailer, with the proper
inflation pressure. See Full-Size Spare
Tire 0368.
Tire Designations
Tire Size
The example shows a typical passenger
vehicle tire size.
Passenger (P-Metric) Tire
(1) Passenger (P-Metric) Tire:The
United States version of a metric tire
sizing system. The letter "P" as the first
character in the tire size means a passenger vehicle tire engineered to
standards set by the U.S. Tire and Rim
Association.
(2) Tire Width
:The 3-digit number
indicates the tire section width in
millimeters from sidewall to sidewall.
(3) Aspect Ratio
:A 2-digit number that
indicates the tire height-to-width
measurements. For example, if the tire
size aspect ratio is 75, as shown in
item (3) of the illustration, it would
mean that the tire's sidewall is
75 percent as high as it is wide.
(4) Construction Code
:A letter code is
used to indicate the type of ply
construction in the tire. The letter "R"
means radial ply construction; the letter
"D" means diagonal or bias ply
construction.
(5) Rim Diameter
:Diameter of the
wheel in inches.
(6) Service Description
:These
characters represent the load index and
speed rating of the tire. The load index
represents the load carrying capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is
certified to carry a load.
Tire Terminology and Definitions
Air Pressure:The amount of air inside
the tire pressing outward on each
square inch of the tire. Air pressure is
expressed in kPa (kilopascal) or psi
(pounds per square inch).
Accessory Weight
:The combined
weight of optional accessories. Some
examples of optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship of a
tire's height to its width.
Belt
:A rubber coated layer of cords
between the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that hold
the tire onto the rim.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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348 Vehicle Care
Warning (Continued)
inflation pressure adjustment for
high-speed operation. When speed limits
and road conditions allow the vehicle to
be driven at high speeds, make sure the
tires are rated for high-speed operation,
are in excellent condition, and are set to
the correct cold tire inflation pressure for
the vehicle load.
Vehicles with tire sizes listed in the High
Speed Operation Inflation Pressures table
require inflation pressure adjustment when
driving the vehicle at speeds of 160 km/h
(100 mph) or higher. Set the cold tire
inflation pressure to the corresponding value
in the table for the tire size on the vehicle. High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
265/65R18 114T 240 kPa (35 psi)
275/55R20 113V (2WD) 270 kPa (39 psi)
275/55R20 113V (4WD) 260 kPa (38 psi) 275/60R20 115T 240 kPa (35 psi)275/50R22 111H 270 kPa (39 psi)
Return the tires to the recommended cold
tire inflation pressure when high-speed
driving has ended. See Vehicle Load Limits
0 222 and
Tire Pressure 0346.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS)
uses radio and sensor technology to check
tire pressure levels. The TPMS sensors
monitor the air pressure in your tires and
transmit tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure
recommended by the vehicle manufacturer on the vehicle placard or tire inflation
pressure label. (If your vehicle has tires of a
different size than the size indicated on the
vehicle placard or tire inflation pressure
label, you should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your vehicle has
been equipped with a tire pressure
monitoring system (TPMS) that illuminates a
low tire pressure telltale when one or more
of your tires is significantly under-inflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and
check your tires as soon as possible, and
inflate them to the proper pressure. Driving
on a significantly under-inflated tire causes
the tire to overheat and can lead to tire

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
Vehicle Care 349
failure. Under-inflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle's handling and stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance, and
it is the driver's responsibility to maintain
correct tire pressure, even if under-inflation
has not reached the level to trigger
illumination of the TPMS low tire pressure
telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined
with the low tire pressure telltale. When the
system detects a malfunction, the telltale
will flash for approximately one minute and
then remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended. TPMS malfunctions may occur for
a variety of reasons, including the
installation of replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Alwayscheck the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
See
Tire Pressure Monitor Operation 0349.
See Radio Frequency Statement 0409.
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a low tire
pressure condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire and
wheel assembly. The TPMS sensors monitor
the air pressure in the tires and transmit the
tire pressure readings to a receiver located
in the vehicle.
When a low tire pressure condition is
detected, the TPMS illuminates the low tire
pressure warning light located on the instrument cluster. If the warning light
comes on, stop as soon as possible and
inflate the tires to the recommended
pressure shown on the Tire and Loading
Information label. See
Vehicle Load Limits
0 222.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC warning
message come on at each ignition cycle
until the tires are inflated to the correct
inflation pressure. If the vehicle has DIC
buttons, tire pressure levels can be viewed.
For additional information and details about
the DIC operation and displays, see Driver
Information Center (DIC) 0119.
The low tire pressure warning light may
come on in cool weather when the vehicle is
first started, and then turn off as the vehicle
is driven. This could be an early indicator
that the air pressure is getting low and
needs to be inflated to the proper pressure.
A Tire and Loading Information label shows
the size of the original equipment tires and
the correct inflation pressure for the tires

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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350 Vehicle Care
when they are cold. SeeVehicle Load Limits
0 222, for an example of the Tire and
Loading Information label and its location.
Also see Tire Pressure 0346.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 351, Tire Rotation 0352 and
Tires 0341.
Caution
Tire sealant materials are not all the
same. A non-approved tire sealant could
damage the TPMS sensors. TPMS sensor
damage caused by using an incorrect tire
sealant is not covered by the vehicle
warranty. Always use only the GM
approved tire sealant available through
your dealer or included in the vehicle.
TPMS Malfunction Light and Message
The TPMS will not function properly if one
or more of the TPMS sensors are missing or
inoperable. When the system detects a
malfunction, the low tire pressure warning
light flashes for about one minute and then
stays on for the remainder of the ignition
cycle. A DIC warning message also displays.
The malfunction light and DIC warning message come on at each ignition cycle
until the problem is corrected. Some of the
conditions that can cause these to come
on are:
.One of the road tires has been replaced
with the spare tire. The spare tire does
not have a TPMS sensor. The malfunction
light and the DIC message should go off
after the road tire is replaced and the
sensor matching process is performed
successfully. See "TPMS Sensor Matching
Process" later in this section.
.The TPMS sensor matching process was
not done or not completed successfully
after rotating the tires. The malfunction
light and the DIC message should go off
after successfully completing the sensor
matching process. See "TPMS Sensor
Matching Process" later in this section.
.One or more TPMS sensors are missing or
damaged. The malfunction light and the
DIC message should go off when the
TPMS sensors are installed and the sensor
matching process is performed
successfully. See your dealer for service.
.Replacement tires or wheels do not match
the original equipment tires or wheels.
Tires and wheels other than those
recommended could prevent the TPMS
from functioning properly. See
Buying
New Tires 0353.
.Operating electronic devices or being near
facilities using radio wave frequencies
similar to the TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning properly, it
cannot detect or signal a low tire pressure
condition. See your dealer for service if the
TPMS malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and audible
alerts outside the vehicle to help when
inflating an underinflated tire to the
recommended cold tire pressure.
When the low tire pressure warning light
comes on: 1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal lamp will flash.