2021 CHEVROLET BLAZER Owner's Manual

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
248 Driving and Operating
Trailer Load Balance
The correct trailer load balance must be
maintained to ensure trailer stability.
Incorrect load balance is a leading cause of
trailer sway.
The trailer tongue weight (1) should be 10–
15% of the loaded trailer weight (2). Some
specific trailer types, such as boat trailers,
fall outside of this range. Always refer to
the trailer owner’s manual for the
recommended trailer tongue weight for each
trailer. Never exceed the maximum loads for
your vehicle, hitch, and trailer.
After loading the trailer, separately weigh
the trailer and then the trailer tongue and
calculate the trailer load balance percentageto see if the weights and distribution are
appropriate for your vehicle. If the trailer
weight is too high, it may be possible to
transfer some of the cargo into your vehicle.
If the trailer tongue weight is too high or
too low, it may be possible to rearrange
some of the cargo inside of the trailer.
Do not exceed the maximum allowable
tongue weight for your vehicle. Use the
shortest hitch extension available to position
the hitch ball closer to your vehicle. This will
help reduce the effect of the trailer tongue
weight on the trailer hitch and the rear axle.
If a cargo carrier is used in the trailer hitch
receiver, choose a carrier that positions the
load as close to the vehicle as possible.
Make sure the total weight, including the
carrier, is no more than half of the
maximum allowable tongue weight for the
vehicle or 227 kg (500 lb), whichever is less.
Ask your dealer for trailering information or
assistance.
Towing Equipment
Hitches
Always use the correct hitch equipment for
your vehicle. Crosswinds, large trucks going
by, and rough roads can affect the trailer
and the hitch.
Never attach rental hitches or other
bumper-type hitches. Only use
frame-mounted hitches that do not attach to
the bumper.
Hitch Cover
To remove the hitch cover, if equipped:
1. Remove the four fasteners on the lower tabs.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Driving and Operating 249
2. Pull the lower edge of the cover toabout a 45 degree angle.
3. Pull the cover downward to disengage the upper attachments.
To reinstall the hitch cover: 1. Hold the cover at a 45 degree angle to the vehicle and push the upper tabs into
the slots in the bumper.
2. Push the bottom of the cover forward until the lower tabs line up with the
lower slots.
3. Snap the hitch cover into place by pushing the upper corners forward.
4. Reinstall the four fasteners on the lower tabs.
Consider using mechanical sway controls
with any trailer. Ask a trailering professional
about sway controls or refer to the trailer
manufacturer's recommendations and
instructions.
Weight-Distributing Hitch Adjustment
A weight-distributing hitch may be useful
with some trailers.
1. Front of the Vehicle
2. Body-to-Ground Distance
When using a weight-distributing hitch,
measure the front fender height above the
front axle distance (2) before and after
connecting the trailer. Adjust the spring bars
until the front fender height distance (2) is
approximately halfway between the first
and second measurements.
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to support
loads while towing a trailer. See Tires
0 287 for instructions on proper tire
inflation.
Safety Chains
Always attach chains between the vehicle
and the trailer, and attach the chains to the
holes on the trailer hitch platform.
Instructions for safety chains may be
provided by the hitch manufacturer or by
the trailer manufacturer.
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave just enough
slack so the combination can turn. Never
allow safety chains to drag on the ground.
Trailer Brakes
Loaded trailers over 450 kg (1,000 lb) must
be equipped with brake systems and with
brakes for each axle. Trailer braking
equipment conforming to Canadian
Standards Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may require
trailers to have their own braking system if
the loaded weight of the trailer exceeds
certain minimums that can vary from state
to state. Read and follow the instructions for
the trailer brakes so they are installed,
adjusted, and maintained properly. Never

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
250 Driving and Operating
attempt to tap into your vehicle's hydraulic
brake system. If you do, both the vehicle
antilock brakes and the trailer brakes may
not function, which could result in a crash.
Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin
connector, is at the rear of the vehicle and
is tied to the vehicle's frame. The harness
requires the installation of a trailer
connector, which is available through your
dealer.
Use only a round, seven-wire connector with
flat blade terminals meeting SAE J2863
specifications for proper electrical
connectivity.
The seven-wire harness contains the
following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Green: Right Stop/Turn Signal
.Brown: Tail/Parking Lamps
.White: Trailer Ground
.Red: Stop Lamp Supply Voltage
.Black: Back Up Lamp Supply Voltage
.Blue: Service BrakesThe fuse for the electric trailer brake circuit
is in the engine compartment fuse block,
but the wires may not be connected. They
should be connected by your dealer or a
qualified service center. To control electric
trailer brakes, a trailer brake controller needs
to be installed on the vehicle by your dealer
or a qualified service center. See electric
brake control wiring provisions.
If a battery outside the vehicle is being
charged, place the vehicle in Tow/Haul
Mode. This will boost the vehicle system
voltage and properly charge the battery.
If the trailer is too light for Tow/Haul Mode,
turn on the non-HID only headlamps as a
second way to boost the vehicle system
voltage and charge the battery.
Electric Trailer Brake Control Wiring
Provisions
Wiring provisions for an aftermarket electric
trailer brake controller are included with the
vehicle as part of the trailer wiring package.
The harness contains the following circuits:
These wiring provisions for an electric trailer
brake controller are included with the
vehicle as part of the trailer wiring package.
The body harness, inside the front driver
side instrument panel, contains blunt cut wires below the headlamp switch for the
electric trailer brake controller. The harness
contains the following wires:
.Blue: Electric Trailer Brakes
.Blue: Battery Feed
.White/Blue: Brake Apply Signal
.Black: Ground
Refer to the aftermarket electric trailer brake
controller owner's manual to determine wire
color coding of the electric trailer brake
controller. The wire colors on the brake
controller may be different from the vehicle.
The electric trailer brake controller should be
installed by your dealer or a qualified
service center.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 251
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeDriver Mode Control 0214.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0210.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Weight of the Trailer” under
Trailer Towing 0245. Tow/Haul Mode is
most useful when towing a heavy trailer or
carrying a large or heavy load:
.Through rolling terrain.
.In stop-and-go traffic.
.In busy parking lots.
Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer Brake
Control (ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC may
also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak light will flash on
the instrument cluster. Reduce vehicle speed
by gradually removing your foot from the
accelerator. If trailer sway continues,
StabiliTrak/ESC can reduce engine torque to
help slow the vehicle. TSC will not function
if StabiliTrak/ESC is turned off. See
Traction
Control/Electronic Stability Control 0213.
{Warning
Trailer sway can result in a crash and in
serious injury or death, even if the
vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing your
foot from the accelerator. Then pull over
to check the trailer and vehicle to help
correct possible causes, including an
improperly or overloaded trailer,
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment 0248 for trailer
ratings and hitch setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
252 Driving and Operating
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blowouts.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blowouts. Never load your trailer
with more weight than the tires are
designed to support. The load rating is on
the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. SeeMalfunction
Indicator Lamp (Check Engine Light) 0100
. A device connected to the DLC —such
as an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating.
The vehicle has an airbag system. Before
attempting to add anything electrical to the
vehicle, see Servicing the Airbag-Equipped
Vehicle 058 and
Adding Equipment to the Airbag-Equipped
Vehicle 059.

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Vehicle Care 253
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 254
California Proposition 65 Warning . . . . . 254
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 254
Accessories and Modifications . . . . . . . . . 254
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 255
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Engine Compartment Overview . . . . . . . . 257
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Oil Life System . . . . . . . . . . . . . . . . 264
Automatic Transmission Fluid . . . . . . . . . 265
Engine Air Filter Life System . . . . . . . . . . 265
Engine Air Cleaner/Filter . . . . . . . . . . . . . . 265
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 267
Engine Overheating . . . . . . . . . . . . . . . . . . . . 271
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Battery - North America . . . . . . . . . . . . . . . 274
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . 275
Automatic Transmission Shift Lock Control Function Check . . . . . . . . . . . . . . 275
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Wiper Blade Replacement . . . . . . . . . . . . . 276 Windshield Replacement . . . . . . . . . . . . . . . 277
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 278
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 278
High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . . . 278
Electrical System
High Voltage Devices and Wiring . . . . . . 279
Electrical System Overload . . . . . . . . . . . . 279
Fuses and Circuit Breakers . . . . . . . . . . . . 280
Engine Compartment Fuse Block . . . . . . 280
Instrument Panel Fuse Block . . . . . . . . . . 284
Rear Compartment Fuse Block . . . . . . . . . 285
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . 288
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Summer Tires . . . . . . . . . . . . . . . . . . . . . . . . . 289
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 289
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 291
Tire Terminology and Definitions . . . . . . 292
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 Tire Pressure Monitor System . . . . . . . . . 296
Tire Pressure Monitor Operation . . . . . . 297
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 300
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 300
When It Is Time for New Tires . . . . . . . . 301
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 302
Different Size Tires and Wheels . . . . . . . 303
Uniform Tire Quality Grading . . . . . . . . . 303
Wheel Alignment and Tire Balance . . . . 305
Wheel Replacement . . . . . . . . . . . . . . . . . . . 305
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 306
Tire Sealant and Compressor Kit . . . . . . . 307
Storing the Tire Sealant and
Compressor Kit . . . . . . . . . . . . . . . . . . . . . . . 313
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 317
Jump Starting
Jump Starting - North America . . . . . . . . 318
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 320
Recreational Vehicle Towing . . . . . . . . . . . 321
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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254 Vehicle Care
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
{Warning
Most motor vehicles, including this one,
as well as many of its service parts and
fluids, contain and/or emit chemicals
known to the State of California to cause(Continued)
Warning (Continued)
cancer and birth defects or other
reproductive harm. Engine exhaust, many
parts and systems, many fluids, and
some component wear by-products
contain and/or emit these chemicals. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0274 and
Jump Starting - North America 0318 and the
back cover.
California Perchlorate Materials
Requirements
Certain types of automotive applications,
such as airbag initiators, seat belt
pretensioners, and lithium batteries
contained in electronic keys, may contain
perchlorate materials. Perchlorate Material –
special handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, and electronic
systems like antilock brakes, traction control,
and stability control. These accessories or
modifications could even cause malfunction
or damage not covered by the vehicle
warranty.
Damage to suspension components caused
by modifying vehicle height outside of
factory settings will not be covered by the
vehicle warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 255
Also, seeAdding Equipment to the
Airbag-Equipped Vehicle 059.
Vehicle Checks
Doing Your Own Service Work
{Warning
It can be dangerous to work on your
vehicle if you do not have the proper
knowledge, service manual, tools,
or parts. Always follow owner’s manual
procedures and consult the service
manual for your vehicle before doing any
service work.
If doing some of your own service work, use
the proper service manual. It tells you much
more about how to service the vehicle than
this manual can. To order the proper service
manual, see Publication Ordering
Information 0356.
This vehicle has an airbag system. Before
attempting to do your own service work,
see Servicing the Airbag-Equipped Vehicle
0 58. If equipped with remote vehicle start, open
the hood before performing any service
work to prevent remote starting the vehicle
accidentally. See
Remote Vehicle Start 013.
Keep a record with all parts receipts and list
the mileage and the date of any service
work performed. See Maintenance Records
0 343.Caution
Even small amounts of contamination can
cause damage to vehicle systems. Do not
allow contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto engine stop/start,
turn the vehicle off before opening the
hood. If the vehicle is on, the engine will
start when the hood is opened. You or
others could be injured.
{Warning
Components under the hood can get hot
from running the engine. To help avoid
the risk of burning unprotected skin,
never touch these components until they
have cooled, and always use a glove or
towel to avoid direct skin contact.
Clear any snow from the hood before
driving.
To open the hood:
1. Pull the hood release lever with the
i. It is on the lower left side of the
instrument panel.