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246 Driving and Operating
See“Trailer Brakes” underTowing
Equipment 0248 to determine if brakes are
required based on your trailer's weight.
The only way to be sure the weight is not
exceeding any of these ratings is to weigh
the tow vehicle and trailer combination,
fully loaded for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously injured
or killed if the trailer is too heavy or the
trailer brakes are inadequate for the load.
The vehicle may be damaged, and the
repairs would not be covered by the
vehicle warranty.
Only tow a trailer if all the steps in this
section have been followed. Ask your
dealer for advice and information about
towing a trailer.
Gross Combined Weight Rating (GCWR)
GCWR is the total allowable weight of the
completely loaded vehicle and trailer
including any fuel, passengers, cargo,
equipment, and accessories. Do not exceed
the GCWR for your vehicle. The GCWR for
the vehicle is on the tow rating chart later
in this section.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0197. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating is
calculated assuming the tow vehicle has a
driver, a front seat passenger, and all
required trailering equipment. This value
represents the heaviest trailer the vehicle
can tow, but it may be necessary to reduce
the trailer weight to stay within the GCW,
GVWR, maximum trailer tongue load,
or GAWR-RR for the vehicle.
Use the tow rating chart to determine how
much the trailer can weigh, based on the
vehicle model, powertrain, and trailering
options.
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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-
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274 Vehicle Care
.Normal brake lining wear. When new
linings are installed, the fluid level goes
back up.
.A fluid leak in the brake hydraulic system.
Have the brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid reservoir cap
and the area around the cap before
removing it.
Do not top off the brake fluid. Adding fluid
does not correct a leak. If fluid is added
when the linings are worn, there will be too
much fluid when new brake linings are
installed. Add or remove fluid, as necessary,
only when work is done on the brake
hydraulic system.
{Warning
If too much brake fluid is added, it can
spill on the engine and burn, if the
engine is hot enough. You or others could
be burned, and the vehicle could be
damaged. Add brake fluid only when
work is done on the brake hydraulic
system. When the brake fluid falls to a low level,
the brake warning light comes on. See
Brake
System Warning Light 0101.
Brake fluid absorbs water over time which
degrades the effectiveness of the brake fluid.
Replace brake fluid at the specified intervals
to prevent increased stopping distance. See
Maintenance Schedule 0332.
What to Add
Use only GM approved DOT 3 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0340.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.
Refer to the replacement number on the
original battery label when a new battery is
needed. For replacement of the battery, see
your dealer.
Stop/Start System
The vehicle has a Stop/Start system to shut
off the engine to help conserve fuel. See
Stop/Start System 0203.
It has an Absorbed Glass Mat (AGM) 12-volt
battery. Installation of a standard 12-volt
battery will result in reduced 12-volt
battery life.
When using a 12-volt battery charger on the
12-volt AGM battery, some chargers have an
AGM battery setting on the charger.
If available, use the AGM setting on the
charger, to limit charge voltage to 14.8 volts.
{Warning
WARNING: Battery posts, terminals, and
related accessories contain lead and lead
compounds, chemicals known to the (Continued)
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Vehicle Care 283
FusesUsage
F50 Fuel system control module/Fuel tank zone
module run/crank
F51 Heated steering wheel
F52 Air conditioning clutch
F53 Coolant pump
F54 –
F55 –
F56 –
F57 Engine control module/ Ignition
F58 Transmission control module/Ignition
F59 Engine control module battery
F60 –
F61 O2 sensor 1/ Aeroshutter/Mass air
flow sensor
F62 Engine control module–odd
F63 O2 sensor 2 Fuses
Usage
F64 Engine control module–even
F65 Engine control module powertrain 1
F66 Engine control module powertrain 2
F67 Engine control module powertrain 3
F68 –
F69 –
F70 –
F71 –
F72 –
F73 –
F74 –
F75 –
F76 –
F77 – Relays
Usage
K1 Starter 1
K2 Run/Crank
K3 Starter 3
K4 –
K5 –
K6 –
K7 Engine control module
K8 Air conditioning
K9 –
K10 Starter 2
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Vehicle Care 287
FusesUsage
F24 –
F25 –
F26 Trailer brake F27 Driver ventilated seat/ Lumbar
F28 Passive entry/Passive start
F29 –
F30 Canister vent F31 –
F32 Heated mirrors
F33 –
F34 Liftgate module F35 Fuel system control module/Fuel tank zone
module
F36 Passenger ventilated seat/Lumbar
F37 –
F38 Window module
F39 Rear closure Fuses
Usage
F40 Memory seat module F41 Automatic occupancy sensor
F42 –
F43 –
F44 –
F45 Liftgate motor
F46 Rear heated seats F47 –
F48 –
F49 –
F50 –
F51 –
F52 Rear drive control 2/ Semi-active dampening
system module
F53 Video
F54 External object calculating/Side blind
zone alert
F55 – Fuses
Usage
F56 Universal remote/Rain sensor
F57 Alarm overhead console/Theft deterrent
Circuit Breakers Usage CB1 –
CB2 –
CB3 Rear auxiliary power outlet
Relays Usage
K1 –
K2 –
Wheels and Tires
Tires
Every new GM vehicle has high-quality
tires made by a leading tire
manufacturer. See the warranty manual
for information regarding the tire
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292 Vehicle Care
(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.
Bias Ply Tire
:A pneumatic tire in which
the plies are laid at alternate angles
less than 90 degrees to the centerline
of the tread.
Cold Tire Pressure
:The amount of air
pressure in a tire, measured in kPa
(kilopascal) or psi (pounds per square
inch) before a tire has built up heat
from driving. See Tire Pressure0294. Curb Weight
:The weight of a motor
vehicle with standard and optional
equipment including the maximum
capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the
sidewall of a tire signifying that the tire
is in compliance with the U.S.
Department of Transportation (DOT)
Motor Vehicle Safety Standards. The
DOT code includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also identify the
tire manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight Rating.
See Vehicle Load Limits 0197.
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294 Vehicle Care
Radial Ply Tire:A pneumatic tire in
which the ply cords that extend to the
beads are laid at 90 degrees to the
centerline of the tread.
Rim
:A metal support for a tire and
upon which the tire beads are seated.
Sidewall
:The portion of a tire between
the tread and the bead.
Speed Rating
:An alphanumeric code
assigned to a tire indicating the
maximum speed at which a tire can
operate.
Traction
:The friction between the tire
and the road surface. The amount of
grip provided.
Tread
:The portion of a tire that comes
into contact with the road.
Treadwear Indicators
:Narrow bands,
sometimes called wear bars, that show
across the tread of a tire when only
1.6 mm (1/16 in) of tread remains. See
When It Is Time for New Tires 0301. UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system
that provides consumers with ratings
for a tire's traction, temperature, and
treadwear. Ratings are determined by
tire manufacturers using government
testing procedures. The ratings are
molded into the sidewall of the tire.
See Uniform Tire Quality Grading 0303.
Vehicle Capacity Weight
:The number
of designated seating positions
multiplied by 68 kg (150 lb) plus the
rated cargo load. See Vehicle Load
Limits 0197.
Vehicle Maximum Load on the Tire
:
Load on an individual tire due to curb
weight, accessory weight, occupant
weight, and cargo weight.
Vehicle Placard
:A label permanently
attached to a vehicle showing the
vehicle capacity weight and the original
equipment tire size and recommended
inflation pressure. See “Tire and Loading
Information Label” underVehicle Load
Limits 0197.
Tire Pressure
Tires need the correct amount of air
pressure to operate effectively.
{Warning
Neither tire underinflation nor
overinflation is good. Underinflated
tires, or tires that do not have
enough air, can result in:
.Tire overloading and overheating,
which could lead to a blowout.
.Premature or irregular wear.
.Poor handling.
.Reduced fuel economy.
Overinflated tires, or tires that have
too much air, can result in:
.Unusual wear.
.Poor handling.
.Rough ride.
.Needless damage from road
hazards.
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296 Vehicle Care
High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
235/65R18 280 kPa (41 psi)
235/55R20 280 kPa (41 psi) 265/45R21 280 kPa (41 psi)
Return the tires to the recommended cold
tire inflation pressure when high-speed
driving has ended. See Vehicle Load Limits
0 197 and
Tire Pressure 0294.
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
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.