2021 GMC SIERRA Dot 4

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 127
than when the oil has just been changed.
It cannot be reset accurately until the next
oil change. To reset, seeEngine Oil Life
System 0332.
Tire Pressure : Shows the approximate
pressures of all four tires. Tire pressure is
displayed in either kilopascal (kPa) or in
pounds per square inch (psi). If the pressure
is low, the value for that tire is shown in
amber. See Tire Pressure Monitor System
0 368 and
Tire Pressure Monitor Operation 0369.
Air Filter Life : Shows an estimate of the
engine air filter’s remaining useful life and
the state of the system. Engine Air Filter Life
95% means 95% of the current air filter life
remains. Messages will display based on the
engine air filter life and the state of the
system. When the REPLACE AT NEXT OIL
CHANGE message displays, the engine air
filter should be replaced at the time of the
next oil change. When the REPLACE SOON
message displays, the engine air filter
should be replaced at the earliest
convenience.
The Air Filter Life display must be reset after
the engine air filter replacement. To reset,
see Engine Air Filter Life System 0333. Brake Pad Life :
This displays an estimate of
the remaining life of the front and rear
brake pads. Messages will display based on
brake pad wear and the state of the system.
Reset the Brake Pad Life display after
replacing the brake pads. See Brake Pad Life
System 0342.
Fuel Economy : Displays average fuel
economy, the best fuel economy over the
selected distance, and a bar graph showing
instantaneous fuel economy.
Press the thumbwheel to change the
selected distance. Press and hold the
thumbwheel while this display is active to
reset the best fuel economy and average
fuel economy. This display can also be reset
by selecting reset in the menu.
Engine Hours (Hourmeter) : Shows the total
number of hours the engine has run. This
display also shows the engine idle hours.
Transmission Fluid Temperature : Shows the
temperature of the automatic transmission
fluid in either degrees Celsius (°C) or degrees
Fahrenheit (°F).
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control (ITBC)
system, the trailer brake display appears in
the DIC. TRAILER GAIN shows the trailer gain setting.
This setting can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected.
TRAILER OUTPUT shows the power output to
the trailer any time a trailer with electric
brakes is connected. Output is displayed as a
bar graph. Dotted lines may appear in the
OUTPUT display if a trailer is not connected.
Off Road :
Displays vehicle pitch and roll
information, road wheel angle, and
four-wheel drive (4WD) status.
Follow Distance : If equipped, the current
follow time to the vehicle ahead is displayed
as a time value on this page.
Driver Assistance : If equipped, shows
information for Lane Keep Assist (LKA) and
Forward Collision Alert (FCA).
Info Page Options : Scroll to choose which
info pages appear on the DIC. Press the
thumbwheel to select or deselect.
Blank Page : Shows no information.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 343
Brake Fluid
The brake master cylinder reservoir is filled
with GM approved DOT 4 brake fluid as
indicated on the reservoir cap. SeeEngine
Compartment Overview 0325 for the
location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum marks
on the brake fluid reservoir.
There are only two reasons why the brake
fluid level in the reservoir may go down:
.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 0117.
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 0409. What to Add
Use only GM approved DOT 4 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants
0418.
{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 shown on
the original battery label when a new
battery is needed. See Engine Compartment
Overview 0325 for battery location.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
362 Vehicle Care
If using winter tires:
.Use tires of the same brand and tread
type on all four wheel positions.
.Use only radial ply tires of the same size,
load range, and speed rating as the
original equipment tires.
Winter tires with the same speed rating as
the original equipment tires may not be
available for H, V, W, Y, and ZR speed rated
tires. If winter tires with a lower speed
rating are chosen, never exceed the tire's
maximum speed capability.
All-Terrain Tires
This vehicle may have all-terrain or
mud-terrain tires. These tires provide good
performance on most road surfaces, weather
conditions, and for off-road driving. See
Off-Road Driving 0215.
The tread pattern on these tires may wear
more unevenly than other tires. Consider
rotating the tires more frequently than at
12 000 km (7,500 mi) intervals if irregular
wear is noted when the tires are inspected.
See Tire Inspection 0373.
Tire Sidewall Labeling
Useful information about a tire is
molded into the sidewall. The examples
show a typical passenger and light
truck tire sidewall.
Passenger (P-Metric)/Spare Tire
(1) Tire Size:The tire size code is a
combination of letters and numbers
used to define a particular tire's width,
height, aspect ratio, construction type,
and service description. See the “Tire
Size” illustration later in this section. (2) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires
designed to GM's specific tire
performance criteria have a TPC
specification code molded onto the
sidewall. GM's TPC specifications meet
or exceed all federal safety guidelines.
(3) DOT (Department of
Transportation)
:The Department of
Transportation (DOT) code indicates that
the tire is in compliance with the U.S.
Department of Transportation Motor
Vehicle Safety Standards.
DOT Tire Date of Manufacture
:The last
four digits of the TIN indicate the tire
manufactured date. The first two digits
represent the week (01-52) and the last
two digits, the year. For example, the
third week of the year 2020 would have
a 4-digit DOT date of 0320. Week 01 is
the first full week (Sunday through
Saturday) of each year.
(4) Tire Identification Number (TIN)
:
The letters and numbers following the
DOT code are the Tire Identification
Number (TIN). The TIN shows the

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 363
manufacturer and plant code, tire size,
and date the tire was manufactured.
The TIN is molded onto both sides of
the tire, although only one side may
have the date of manufacture.
(5) Tire Ply Material
:The type of cord
and number of plies in the sidewall and
under the tread.
(6) Uniform Tire Quality Grading
(UTQG)
:Tire manufacturers are
required to grade tires based on three
performance factors: treadwear,
traction, and temperature resistance.
For more information, see Uniform Tire
Quality Grading 0377.
(7) Maximum Cold Inflation Load
Limit
:Maximum load that can be
carried and the maximum pressure
needed to support that load. For
information on recommended tire
pressure see Tire Pressure 0367 and
Vehicle Load Limits 0222.
(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 0390.
Light Truck (LT-Metric) Tire
(1) Tire Size:The tire size code is a
combination of letters and numbers
used to define a particular tire's width,
height, aspect ratio, construction type,
and service description. See the “Tire
Size” illustration later in this section for
more detail.
(2) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires
designed to GM's specific tire performance criteria have a TPC
specification code molded onto the
sidewall. GM's TPC specifications meet
or exceed all federal safety guidelines.
(3) Dual Tire Maximum Load
:
Maximum load that can be carried and
the maximum pressure needed to
support that load when used in a dual
configuration. For information on
recommended tire pressure see
Tire
Pressure 0367 and
Vehicle Load Limits 0222.
(4) DOT (Department of
Transportation)
:The Department of
Transportation (DOT) code indicates that
the tire is in compliance with the U.S.
Department of Transportation Motor
Vehicle Safety Standards.
DOT Tire Date of Manufacture
:The last
four digits of the TIN indicate the tire
manufactured date. The first two digits
represent the week (01-52) and the last
two digits, the year. For example, the
third week of the year 2020 would have

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
364 Vehicle Care
a 4-digit DOT date of 0320. Week 01 is
the first full week (Sunday through
Saturday) of each year.
(5) Tire Identification Number (TIN)
:
The letters and numbers following the
DOT code are the Tire Identification
Number (TIN). The TIN shows the
manufacturer and plant code, tire size,
and date the tire was manufactured.
The TIN is molded onto both sides of
the tire, although only one side may
have the date of manufacture.
(6) Tire Ply Material
:The type of cord
and number of plies in the sidewall and
under the tread.
(7) Single Tire Maximum Load
:
Maximum load that can be carried and
the maximum pressure needed to
support that load when used as a
single. For information on
recommended tire pressure see Tire
Pressure 0367 and
Vehicle Load Limits 0222.
Tire Designations
Tire Size
The examples show a typical passenger
vehicle and light truck 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 tire 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.
Light Truck (LT-Metric) Tire

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 365
(1) Light Truck (LT-Metric) Tire:The
United States version of a metric tire
sizing system. The letters LT as the first
two characters in the tire size mean a
light truck 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 light truck (LT-Metric) tire
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) Load Range
:Load Range.
(7) Service Description
:The service
description indicates the load index and
speed rating of a tire. If two numbers
are given as in the example, 120/116,
then this represents the load index for
single versus dual wheel usage (single/
dual). 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 Pressure0367.
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)

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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366 Vehicle Care
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 0222.
GAWR FRT
:Gross Axle Weight Rating
for the front axle. See Vehicle Load
Limits 0222.
GAWR RR
:Gross Axle Weight Rating
for the rear axle. See Vehicle Load
Limits 0222.
Intended Outboard Sidewall
:The side
of an asymmetrical tire that must
always face outward when mounted on
a vehicle.
Kilopascal (kPa)
:The metric unit for air
pressure.
Light Truck (LT-Metric) Tire
:A tire used
on light duty trucks and some
multipurpose passenger vehicles. Load Index
:An assigned number
ranging from 1 to 279 that corresponds
to the load carrying capacity of a tire.
Maximum Inflation Pressure
:The
maximum air pressure to which a cold
tire can be inflated. The maximum air
pressure is molded onto the sidewall.
Maximum Load Rating
:The load rating
for a tire at the maximum permissible
inflation pressure for that tire.
Maximum Loaded Vehicle Weight
:The
sum of curb weight, accessory weight,
vehicle capacity weight, and production
options weight.
Normal Occupant Weight
:The number
of occupants a vehicle is designed to
seat multiplied by 68 kg (150 lb). See
Vehicle Load Limits 0222.
Occupant Distribution
:Designated
seating positions.
Outward Facing Sidewall
:The side of
an asymmetrical tire that has a
particular side that faces outward when
mounted on a vehicle. The side of the
tire that contains a whitewall, bears white lettering, or bears manufacturer,
brand, and/or model name molding
that is higher or deeper than the same
moldings on the other sidewall of
the tire.
Passenger (P-Metric) Tire
:A tire used
on passenger cars and some light duty
trucks and multipurpose vehicles.
Recommended Inflation Pressure
:
Vehicle manufacturer's recommended
tire inflation pressure as shown on the
tire placard. See Tire Pressure0367 and
Vehicle Load Limits 0222.
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.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 375
Lightly coat the inner diameter of the
wheel hub opening with wheel bearing
grease after a wheel change or tire
rotation to prevent corrosion or rust
build-up.
{Warning
Do not apply grease to the wheel
mounting surface, wheel conical
seats, or the wheel nuts or bolts.
Grease applied to these areas could
cause a wheel to become loose or
come off, resulting in a crash.
When It Is Time for New Tires
Factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road
conditions affect the wear rate of the tires.
Treadwear indicators are one way to tell
when it is time for new tires. Treadwear
indicators appear when the tires have only
1.6 mm (1/16 in) or less of tread remaining.
See Tire Inspection 0373 and
Tire Rotation 0374 for additional
information.
The rubber in tires ages over time. This also
applies to the spare tire, if the vehicle has
one, even if it is never used. Multiple factors
including temperatures, loading conditions,
and inflation pressure maintenance affect
how fast aging takes place. GM recommends
that tires, including the spare if equipped,
be replaced after six years, regardless of
tread wear. To identify the age of a tire, use
the tire manufacture date, which is the last four digits of the DOT Tire Identification
Number (TIN) molded into one side of the
tire sidewall. The last four digits of the TIN
indicate the tire manufactured date. The
first two digits represent the week and the
last two digits, the year. For example, the
third week of the year 2020 would have a
4-digit DOT date of 0320. Week 01 is the
first full week (Sunday through Saturday) of
each year.
Vehicle Storage
Tires age when stored normally mounted on
a parked vehicle. Park a vehicle that will be
stored for at least a month in a cool, dry,
clean area away from direct sunlight to slow
aging. This area should be free of grease,
gasoline, or other substances that can
deteriorate rubber.
Parking for an extended period can cause
flat spots on the tires that may result in
vibrations while driving. When storing a
vehicle for at least a month, remove the
tires or raise the vehicle to reduce the
weight from the tires.