2016 GMC SIERRA light

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
340 Driving and Operating
Vehicle SeriesTrailer WeightWeight-Distributing Hitch
Usage Hitch Distribution
1500 Up to 3175 kg (7,000 lb) OptionalRefer to trailer
manufacturer ’s
recommendation
1500 Over 3175 kg (7,000 lb) Required50%
2500/3500 Up to 8165 kg (18,000 lb) OptionalRefer to trailer
manufacturer ’s
recommendation
1. Front of Vehicle
2. Body to Ground Distance
When using a weight-distributing
hitch, measure distance (2) before
coupling the trailer to the hitch ball.
Measure the height again after the
trailer is coupled and adjust the
spring bars so the distance (2) is as
close as possible to halfway
between the two measurements.
Fifth-Wheel and Gooseneck
Trailering
Fifth-wheel and gooseneck trailers
can be used with many pickup
models. These trailers place a
larger percentage of the weight
(kingpin weight) on the tow vehicle than conventional trailers. Make
sure this weight does not cause the
vehicle to exceed GAWR or GVWR.
Fifth-wheel or gooseneck kingpin
weight should be 15 to 25% of the
trailer weight up to the maximum
amount specified in the trailering
chart for the vehicle. See
“Weight of
the Trailer” underTrailer
Towing 0325.
The hitch should be located in the
pickup bed so that its centerline is
over or slightly in front of the rear
axle. Take care that it is not so far
forward that it will contact the back
of the cab in sharp turns. This is
especially important for short box

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
342 Driving and Operating
behind the spare tire mount. The
harness requires the installation of a
trailer connector, which is available
through your dealer.
Heavy-Duty Trailer Wiring Harness
Package
For vehicles equipped with
heavy-duty trailering, the harness
connector is mounted in the bumper.
For vehicles with the 5th wheel/
gooseneck trailer package, the
harness connector is mounted on
the inside of the pickup bed behind
the rear wheel.
The seven-wire harness contains
the following trailer circuits:
.Green/Violet: Left Stop/Turn
Signal
. Yellow/Gray: Right Stop/Turn
Signal
. Gray/Brown: Taillamps/Parking
Lamps
. White: Ground
. White/Green: Back-up Lamps .
Red/Green: Battery Feed
. Dark Blue: Trailer Brake
To help charge a remote
(non-vehicle) battery, press the Tow/
Haul Mode button at the end of the
shift lever. If the trailer is too light for
Tow/Haul Mode, turn on the
headlamps to help charge the
battery.
Camper/Fifth-Wheel Trailer Wiring
Package
For vehicles without the 5th wheel/
gooseneck tralier package,
seven-wire camper harness is under
the rear bumper, attached to the
frame near the rear crossmember.
A connector must be added to the
wiring harness that connects to the
camper.
The harness contains the following
camper/trailer circuits:
. Green/Violet: Left Stop/Turn
Signal
. Yellow/Gray: Right Stop/Turn
Signal
. Gray/Brown: Taillamps/Parking
Lamps

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 343
.White: Ground
. White/Green: Back-up Lamps
. Red/Green: Battery Feed
. Dark Blue: Trailer Brake
If the vehicle is equipped with the
heavy-duty trailering option, see
“Heavy-Duty Trailer Wiring Harness
Package” earlier in this section.
When the camper-wiring harness is
ordered without the heavy-duty
trailering package, a seven-wire
harness with a seven-pin connector
is at the rear of the vehicle and is
tied to the vehicle's frame.
Electric Brake Control Wiring
Provisions
These wiring provisions are
included with the vehicle as part of
the trailer wiring package. These
provisions are for an electric brake
controller.
The harness should be installed by
your dealer or a qualified service
center.
Tow/Haul Mode
Pressing this button at the end of
the shift lever turns on and off the
Tow/Haul Mode.
This indicator light on the instrument
cluster comes on when the Tow/
Haul Mode is on. Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. See
Tow/Haul
Mode 0292.
Tow/Haul 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 0325. Tow/Haul is
most useful under the following
driving conditions:
. When pulling a heavy trailer or a
large or heavy load through
rolling terrain.
. When pulling a heavy trailer or a
large or heavy load in
stop-and-go traffic.
. When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired.
Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
at all will not cause damage.
However, there is no benefit to the

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
348 Driving and Operating
A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak have a
TSC feature. Trailer sway is
unintended side-to-side motion of a
trailer while being towed. 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 the
vehicle is equipped with the
Integrated Trailer Brake Control
(ITBC) system, and the trailer has
the electric actuated brake system,
StabiliTrak may also apply the trailer
brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on theinstrument cluster. Vehicle speed
must be reduced. If trailer sway
continues, StabiliTrak can reduce
engine torque to help slow the
vehicle. See
Traction Control/
Electronic Stability Control 0303.
{Warning
Even if the vehicle is equipped
with TSC, trailer sway could result
in loss of control and the vehicle
could crash. If excessive trailer
sway is detected, slow down to a
safe speed. Check the trailer and
vehicle to help correct possible
causes. These could include an
improperly or overloaded trailer,
unrestrained cargo, improper
trailer hitch configuration,
excessive vehicle-trailer speed,
or improperly inflated or incorrect
vehicle or trailer tires. See Towing
Equipment 0339 for trailer ratings
and hitch setup
recommendations. Adding non-dealer accessories can
affect the vehicle performance. See
Accessories and
Modifications
0356.

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 349
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)
0 141. 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 085 and Adding Equipment
to the Airbag-Equipped
Vehicle 085.
For information on wiring auxiliary
switches, see www.gmupfitter.com
or contact your dealer.
Adding a Snow Plow or
Similar Equipment
Caution
Do not exceed 64 km/h (40 mph)
with a snow plow mounted to the
vehicle. The vehicle could
overheat and be damaged.
Before installing a snow plow on the
vehicle, here are some things you
need to know:
Caution
If the vehicle does not have the
snow plow prep package, adding
a plow can damage the vehicle,
and the repairs would not be
covered by warranty. Unless the
vehicle was built to carry a snow
plow, do not add one to the
vehicle. If the vehicle has the
snow plow prep package, called
RPO VYU, then the payload the
vehicle can carry will be reduced (Continued)

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
354 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 355
California Proposition65 Warning . . . . . . . . . . . . . . . . . 355
California Perchlorate Materials Requirements . . . . . 356
Accessories and Modifications . . . . . . . . . . . . . . . . 356
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 357
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 357
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 358
Engine Oil . . . . . . . . . . . . . . . . . . . . 363
Engine Oil Life System . . . . . . . 366
Automatic Transmission Fluid (6 Speed Transmission) . . . . . 367
Automatic Transmission Fluid (8 Speed Transmission) . . . . . 370
Engine Air Cleaner/Filter . . . . . . 370
Cooling System . . . . . . . . . . . . . . 371
Engine Coolant . . . . . . . . . . . . . . . 373
Engine Overheating . . . . . . . . . . 375
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 377
Engine Fan . . . . . . . . . . . . . . . . . . . 377 Power Steering Fluid (1500
Series) . . . . . . . . . . . . . . . . . . . . . . 378
Power Steering Fluid (2500/ 3500 Series) . . . . . . . . . . . . . . . . 378
Washer Fluid . . . . . . . . . . . . . . . . . 379
Brakes . . . . . . . . . . . . . . . . . . . . . . . 380
Brake Fluid . . . . . . . . . . . . . . . . . . . 380
Battery - North America . . . . . . 382
Four-Wheel Drive . . . . . . . . . . . . . 382
Front Axle . . . . . . . . . . . . . . . . . . . . 383
Rear Axle . . . . . . . . . . . . . . . . . . . . 384
Noise Control System . . . . . . . . 385
Starter Switch Check . . . . . . . . . 386
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 386
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 387
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 387
Wiper Blade Replacement . . . . 387
Glass Replacement . . . . . . . . . . 388
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 388
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 388
Halogen Bulbs . . . . . . . . . . . . . . . . 388
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 388 LED Lighting . . . . . . . . . . . . . . . . . 389
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 389
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 390
Replacement Bulbs . . . . . . . . . . . 391
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 391
Electrical System Overload . . . 391
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 392
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 392
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 395
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 397
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 399
All-Season Tires . . . . . . . . . . . . . . 400
Winter Tires . . . . . . . . . . . . . . . . . . 400
Low-Profile Tires . . . . . . . . . . . . . 401
All-Terrain Tires . . . . . . . . . . . . . . . 401
Tire Sidewall Labeling . . . . . . . . 401
Tire Designations . . . . . . . . . . . . . 404
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 405

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
370 Vehicle Care
Consistency of Readings
Always check the fluid level at least
twice using the procedure described
previously. Consistency (repeatable
readings) is important to maintaining
proper fluid level. If readings are still
inconsistent, contact the dealer.
Automatic Transmission
Fluid (8 Speed
Transmission)
When to Check and Change
Automatic Transmission Fluid
It is usually not necessary to check
the transmission fluid level. The only
reason for fluid loss is a
transmission leak or overheated
transmission. This vehicle is not
equipped with a transmission fluid
level dipstick. There is a special
procedure for checking and
changing the transmission fluid in
these vehicles. Because this
procedure is difficult, this should be
done at the dealer. Contact the
dealer for additional information or
the procedure can be found in theservice manual. See
Service
Publications Ordering
Information 0481.
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
automatic transmission fluid listed
in Recommended Fluids and
Lubricants 0463.
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 454. Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0463.
Engine Air Cleaner/Filter
If the vehicle has a diesel engine,
see “8-Cylinder Pickup Models”
under “Engine Air Cleaner/Filter” inthe Duramax diesel supplement for
the correct inspection and
replacement procedures.
The engine air cleaner/filter is near
the center of the engine
compartment. See
Engine
Compartment Overview 0358.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air filter, see
Maintenance Schedule 0454.
How to Inspect 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. Remove the engine air
cleaner/filter. Lightly tap and shake
the engine air cleaner/filter (away
from the vehicle), to release loose
dust and dirt. Inspect the engine air
cleaner/filter for damage, and
replace if damaged. Do not clean

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Vehicle Care 375
Light-Duty
Coolant Surge Tank
Pressure CapHeavy-Duty
Coolant Surge Tank
Pressure Cap
1. Remove the coolant surge tank pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means
there is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixture to the FULL
COLD mark. 4. With the coolant surge tank
pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
FULL COLD mark.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1-6.
Caution
If the pressure cap is not tightly
installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. See Engine Coolant
Temperature Gauge 0135.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC). See
Engine Cooling System Messages
0 154 andEngine Power
Messages 0155.