2021 GMC SIERRA end cap

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 319
Caution (Continued)
one to the vehicle. If the vehicle has RPO
VYU, then the payload the vehicle can
carry will be reduced when a snow plow
is installed. The vehicle can be damaged
if either the front or rear axle ratings or
the Gross Vehicle Weight Rating (GVWR)
are exceeded.
The plow the vehicle can carry depends on
many things, such as:
.The options the vehicle came with, and
the weight of those options.
.The weight and number of passengers to
be carried.
.The weight of items added to the vehicle,
like a tool box or truck cap.
.The total weight of any additional cargo
to be carried.
To safely carry a snow plow on the vehicle:
.With a snow plow attached, the engine
coolant temperature gauge may show a
higher temperature than while driving
without one. The snow plow could block
the airflow to the radiator. This could be
more noticeable as vehicle speed
increases. At speeds above 72 km/h
(45 mph), this may cause the engine coolant to overheat. Move or angle the
snow plow blade to allow increased
airflow to the radiator.
.To increase the airflow, move the snow
plow blade position.
.If driving more than 24 km/h (15 mi),
angle the plow blade position.
.Make sure the weight on the front and
rear axles does not exceed the axle rating
for each.
.Follow the snowplow manufacturer’s
recommendations for any rear ballast that
may be required. Rear ballast may be
required to ensure a proper front and rear
weight distribution ratio even though the
actual weight at the front axle may be
less than the front axel rating.
.The snowplow manufacturer or installer
can assist in determining the amount of
rear ballast required to ensure that the
vehicle with the attached snowplow does
not exceed the GVW rating, the front and
rear axle ratings, or the front and rear
weight distribution ratio.
Front axle reserve capacity is the difference
between the Front Gross Axle Weight
Rating (GAWR) and the front axle weight of
the vehicle with full fuel, passengers, and any other cargo. This is the amount of
weight that can be added to the front axle
before reaching the Front GAWR.
To calculate the amount of weight any front
accessory, such as a snow plow, is adding to
the front axle, use this formula:
(W x (A + W.B.)) /W.B.= Weight the accessory
is adding to the front axle.
Where:
IW = Weight of added accessory
IA = Distance that the accessory is in
front of the front axle
IW.B. = Vehicle Wheelbase

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
320 Driving and Operating
For example, adding a 318 kg (700 lb) snow
plow actually adds more than 318 kg (700 lb)
to the front axle. Using the formula, if the
snow plow is 122 cm (4 ft) in front of the
front axle and the wheelbase is 305 cm
(10 ft), then:IW = 318 kg (700 lb)
IA = 122 cm (4 ft)
IW.B. = 305 cm (10 ft)
(W x (A + W.B.)/W.B. = (318 x (122 + 305))/305
= 445 kg (980 lb)
This means if the front axle reserve capacity
is more than 445 kg (980 lb), the snow plow
could be added without exceeding the
front GAWR.
Heavier equipment can be added on the
front of the vehicle if less cargo or fewer
passengers are carried, or by positioning
cargo toward the rear. This reduces the load
on the front. However, the front GAWR, rear
GAWR, and Gross Vehicle Weight
Rating (GVWR) must never be exceeded.{Warning
On some vehicles that have certain front
mounted equipment, such as a snow
plow, it may be possible to load the front
axle to the front Gross Axle Weight
Rating (GAWR) but not have enough
weight on the rear axle to have proper
braking performance. If the brakes cannot
work properly, the vehice could crash.
Always follow the snow plow
manufacturer or installer's
recommendation for rear ballast to
ensure a proper front and rear weight
distribution ratio. Maintaining a proper
front and rear weight distribution ratio is
necessary to provide proper braking
performance.
See your dealer for additional advice and
information about using a snow plow on the
vehicle. Also, see Vehicle Load Limits 0222.
Pickup Conversion to Chassis Cab
We are aware that some vehicle owners
might consider having the pickup box
removed and a commercial or recreational
body installed. Owners should be aware
that, as manufactured, there are differences
between a chassis cab and a pickup with the
box removed which could affect vehicle
safety. The components necessary to adapt
a pickup to permit its safe use with a
specialized body should be installed by the
body builder.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 331
When to Add Engine Oil
If the oil is below the cross-hatched area at
the tip of the dipstick and the engine has
been off for at least 15 minutes, add 1 L
(1 qt) of the recommended oil and then
recheck the level. See“Selecting the Right
Engine Oil” later in this section for an
explanation of what kind of oil to use. For
engine oil crankcase capacity, see Capacities
and Specifications 0424.
Caution
Do not add too much oil. Oil levels above
or below the acceptable operating range
shown on the dipstick are harmful to the
engine. If the oil level is above the
operating range (i.e., the engine has so
much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range), the engine could be
(Continued)
Caution (Continued)
damaged. Drain the excess oil or limit
driving of the vehicle, and seek a service
professional to remove the excess oil.
See Engine Compartment Overview 0325 for
the location of the engine oil fill cap.
Add enough oil to put the level somewhere
in the proper operating range. Push the
dipstick all the way back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil depends on
both the proper oil specification and
viscosity grade. See Recommended Fluids
and Lubricants 0418.
Specification
Use full synthetic engine oils that meet the
dexos1 specification. Engine oils that have
been approved by GM as meeting the
dexos1 specification are marked with the
dexos1 approved logo.
Caution
Failure to use the recommended engine
oil or equivalent can result in engine
damage not covered by the vehicle
warranty.
Viscosity Grade
Use SAE 0W-20 viscosity grade engine oil for
the 5.3L and 6.2L V8 engines.
Use SAE 5W-30 viscosity grade engine oil for
the 2.7L L4, and 4.3L V6 engines. Cold
Temperature Operation: In an area of
extreme cold, where the temperature falls
below −29 °C (−20 °F), use SAE 0W-30 oil. An
oil of this viscosity grade will provide easier
cold starting for the engine at extremely
low temperatures.
When selecting an oil of the appropriate
viscosity grade, it is recommended to select
an oil of the correct specification. See
“Specification” earlier in this section.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 339
In addition, there are ENGINE OVERHEATED
STOP ENGINE, ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS REDUCED
messages in the Driver Information
Center (DIC).
If the decision is made not to lift the hood
when this warning appears, get service help
right away. SeeRoadside Assistance Program
0 431.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface.
2.7L L4, 4.3L V6, 5.3L V8, and 6.2L V8 Engines
Check to see if the engine cooling fans are
running. If the engine is overheating, the
fans should be running. If they are not, do
not continue to run the engine and have the
vehicle serviced.
If the engine or transmission detects an
impending hot fluid condition, then the
transmission may force upshifts to limit
temperatures. Downshifts may also be
prevented in this instance. Normal operation
may continue unless the display indicates
there is a hot condition and engine should
be idled.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.
The 2.7L L4 engine will shut down
automatically if the ENGINE OVERHEATED
STOP ENGINE message displays.
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; see Trailer Towing0293.
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 temperature overheat 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.

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
354 Vehicle Care
Lift the cover to access the fuse block.
Caution
Spilling liquid on any electrical
component on the vehicle may damage
it. Always keep the covers on any
electrical component.
A fuse puller is available in the left
instrument panel end cap.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.
Fuses Usage
1 High-beam left
2 High-beam right Fuses
Usage
3 Headlamp left
4 Headlamp right

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 357
Instrument Panel Fuse Block (Left)
The left instrument panel fuse block access
door is on the driver side edge of the
instrument panel.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.
Pull off the cover to access the fuse block.
A fuse puller is available in the left
instrument panel end cap.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
F1 Rear heated seats left/right
F3 –
F4 –
F5 Spare/MFEG
F6 Heated and ventilated seats left/right
F8 –
F9 Passive entry passive start/ Spare
F10 –
F11 –
F12 Passenger power seat
F13 Export power take off/ Special equipment option 1
F14 –
F15 –
F16 AMP F17 –
F18 –

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