
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Instruments and Controls 145
Transmission
Temperature Gauge
Metric Standard Theme English Standard Theme
This gauge appears when the
vehicle is in Tow/Haul Mode and
shows the transmission fluid
temperature. If the gauge is reading
in the red area and/or a message
appears in the Driver Information
Center (DIC), the vehicle must be
stopped and the cause checked.
One possible cause is a low fluid
level in the transmission. CautionDo not drive the vehicle while the
transmission fluid is overheating,
or the transmission can be
damaged. This could lead to
costly repairs that would not be
covered by the warranty.
Voltmeter Gauge
Standard Theme
When the ignition is on, this gauge
indicates the battery voltage.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
158 Instruments and Controls
Cruise Control Light For vehicles with cruise control, the
cruise control light is white when the
cruise control is on and ready, and
turns green when the cruise control
is set and active.
The light turns off when the cruise
control is turned off. See Cruise
Control 0 285 . Door Ajar Light This light comes on when a door is
open or not securely latched. Before
driving, check that all doors are
properly closed.
Information Displays Driver Information Center
(DIC) (Base Level Cluster) The DIC displays are shown in the
center of the instrument cluster. The
displays show the status of many
vehicle systems. The trip odometer
reset stem in the instrument cluster
is used to access the DIC menu
items.
DIC Menu Items Turn the trip odometer reset stem to
scroll through the following menu
items:
.
Digital Speedometer
.
Trip
.
Fuel Range
.
Average Fuel Economy
.
Tire Pressure
.
Remaining Oil Life
.
Transmission Fluid Temperature
.
Trailer Brake
.
Hourmeter

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 245
Hill and Mountain Roads Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips include:
.
Keep the vehicle serviced and in
good shape.
.
Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.
Shift to a lower gear when going
down steep or long hills.
{ WarningUsing the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope. { WarningCoasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
loss of steering assist. Always
have the engine running and the
vehicle in gear.
.
Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the
center line.
.
Be alert on top of hills;
something could be in your lane
(e.g., stalled car, accident).
.
Pay attention to special road
signs (e.g., falling rocks area,
winding roads, long grades,
passing or no-passing zones)
and take appropriate action. Winter Driving Driving on Snow or Ice Snow or ice between the tires and
the road creates less traction or
grip, so drive carefully. Wet ice can
occur at about 0 °C (32 °F) when
freezing rain begins to fall. Avoid
driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.
Accelerate gently. Accelerating
too quickly causes the wheels to
spin and makes the surface
under the tires slick.
.
Turn on Traction Control. See
Traction Control/Electronic
Stability Control 0 282 .
.
The Antilock Brake System
(ABS) improves vehicle stability
during hard stops, but the
brakes should be applied sooner
than when on dry pavement.
See Antilock Brake System
(ABS) 0 280 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 307Maintenance when Trailer
Towing The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule 0 448 .
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 363 . Trailer Towing If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Do not tow a trailer during break-in.
See New Vehicle Break-In 0 255 .
{ WarningThe driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly. For
example, if the trailer is too heavy
or the trailer brakes are
inadequate for the load, the
vehicle may not stop as expected.
The driver and passengers could
be seriously injured. The vehicle
may also be damaged; the
resulting repairs would not be
covered by the vehicle warranty.
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle. CautionPulling a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
See Vehicle Load Limits 0 248 for
more information about the vehicle's
maximum load capacity.
To identify the trailering capacity of
the vehicle, read the information in
“ Weight of the Trailer ” later in this
section.
Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability, and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 341
Vehicle Care General Information General Information . . . . . . . . . . 342
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 343
California Perchlorate
Materials Requirements . . . . . 343
Accessories and
Modifications . . . . . . . . . . . . . . . . 343
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 344
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 344
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 345
Engine Oil . . . . . . . . . . . . . . . . . . . . 350
Engine Oil Life System . . . . . . . 353
Automatic Transmission Fluid
(6-Speed Transmission) . . . . . 354
Automatic Transmission Fluid
(8-Speed Transmission) . . . . . 357
Engine Air Cleaner/Filter . . . . . . 358
Cooling System . . . . . . . . . . . . . . 359
Engine Overheating . . . . . . . . . . 363
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 364
Engine Fan . . . . . . . . . . . . . . . . . . . 365 Power Steering Fluid (1500
Series) . . . . . . . . . . . . . . . . . . . . . . 365
Power Steering Fluid (2500/
3500 Series) . . . . . . . . . . . . . . . . 365
Washer Fluid . . . . . . . . . . . . . . . . . 366
Brakes . . . . . . . . . . . . . . . . . . . . . . . 367
Brake Fluid . . . . . . . . . . . . . . . . . . . 368
Battery - North America . . . . . . 369
Four-Wheel Drive . . . . . . . . . . . . . 370
Front Axle . . . . . . . . . . . . . . . . . . . . 370
Rear Axle . . . . . . . . . . . . . . . . . . . . 371
Noise Control System . . . . . . . . 373
Starter Switch Check . . . . . . . . . 374
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 375
Wiper Blade Replacement . . . . 375
Windshield Replacement . . . . . 376
Gas Strut(s) . . . . . . . . . . . . . . . . . . 376
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 377
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 378
Halogen Bulbs . . . . . . . . . . . . . . . . 378 High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . 378
LED Lighting . . . . . . . . . . . . . . . . . 378
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 378
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 380
Electrical System High Voltage Devices and
Wiring . . . . . . . . . . . . . . . . . . . . . . . 380
Electrical System Overload . . . 380
Fuses and Circuit Breakers . . . 381
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 381
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 385
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 386
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 389
All-Season Tires . . . . . . . . . . . . . . 389
Winter Tires . . . . . . . . . . . . . . . . . . 390
Low-Profile Tires . . . . . . . . . . . . . 390
All-Terrain Tires . . . . . . . . . . . . . . . 391
Tire Sidewall Labeling . . . . . . . . 391
Tire Designations . . . . . . . . . . . . . 393

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
346 Vehicle Care 1. Positive (+) Terminal. See
Jump Starting - North America
0 426 .
2. Battery - North America 0 369 .
3. Coolant Surge Tank and
Pressure Cap. See Cooling
System 0 359 .
4. Engine Air Cleaner/Filter 0 358 .
5. Automatic Transmission
Dipstick (If Equipped). See
“ How to Check Automatic
Transmission Fluid ” under
Automatic Transmission Fluid
(6-Speed Transmission) 0 354
or Automatic Transmission
Fluid (8-Speed Transmission)
0 357 . 6. Remote Negative ( – ) Location.
See Jump Starting - North
America 0 426 .
7. Engine Cooling Fans (Out of
View). See Cooling System
0 359 .
8. Engine Oil Fill Cap. See “ When
to Add Engine Oil ” under
Engine Oil 0 350 .
9. Engine Oil Dipstick. See
“ Checking Engine Oil ” under
Engine Oil 0 350 . 10. Brake Fluid Reservoir. See
Brake Fluid 0 368 .
11. Windshield Washer Fluid
Reservoir. See “ Adding Washer
Fluid ” under Washer Fluid
0 366 .
12. Engine Compartment Fuse
Block 0 381 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
348 Vehicle Care 1. Positive (+) Terminal. See
Jump Starting - North America
0 426 .
2. Battery - North America 0 369 .
3. Coolant Surge Tank and
Pressure Cap. See Cooling
System 0 359 .
4. Engine Air Cleaner/Filter 0 358 .
5. Automatic Transmission
Dipstick (If Equipped). See
“ How to Check Automatic
Transmission Fluid ” under
Automatic Transmission Fluid
(6-Speed Transmission) 0 354
or Automatic Transmission
Fluid (8-Speed Transmission)
0 357 . 6. Remote Negative ( – ) Location
(Out of View). See Jump
Starting - North America 0 426 .
7. Engine Cooling Fans (Out of
View). See Cooling System
0 359 .
8. Engine Oil Fill Cap. See “ When
to Add Engine Oil ” under
Engine Oil 0 350 .
9. Engine Oil Dipstick. See
“ Checking Engine Oil ” under
Engine Oil 0 350 . 10. Windshield Washer Fluid
Reservoir. See “ Adding Washer
Fluid ” under Washer Fluid
0 366 .
11. Brake Fluid Reservoir. See
Brake Fluid 0 368 .
12. Engine Compartment Fuse
Block 0 381 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
350 Vehicle Care 1. Positive (+) Terminal. See
Jump Starting - North America
0 426 .
2. Battery - North America 0 369 .
3. Coolant Surge Tank and
Pressure Cap. See Cooling
System 0 359 .
4. Engine Air Cleaner/Filter 0 358 .
5. Automatic Transmission
Dipstick (If Equipped). See
“ How to Check Automatic
Transmission Fluid ” under
Automatic Transmission Fluid
(6-Speed Transmission) 0 354
or Automatic Transmission
Fluid (8-Speed Transmission)
0 357 .
6. Engine Oil Dipstick. See
“ Checking Engine Oil ” under
Engine Oil 0 350 .
7. Engine Oil Fill Cap. See “ When
to Add Engine Oil ” under
Engine Oil 0 350 .
8. Engine Cooling Fan (Out of
View). See Cooling System
0 359 . 9. Remote Negative ( – ) Location.
See Jump Starting - North
America 0 426 .
10. Power Steering Fluid
Reservoir. See Power Steering
Fluid (1500 Series) 0 365 or
Power Steering Fluid (2500/
3500 Series) 0 365 .
11. Windshield Washer Fluid
Reservoir. See “ Adding Washer
Fluid ” under Washer Fluid
0 366 .
12. Brake Fluid Reservoir. See
Brake Fluid 0 368 .
13. Auxiliary Battery (If Equipped).
See Battery - North America
0 369 .
14. Engine Compartment Fuse
Block 0 381 .
If the vehicle has a diesel engine
and/or an Allison Transmission, see
the Duramax diesel supplement.
For an eAssist vehicle, see the
Silverado/Sierra supplement. Engine Oil For diesel engine vehicles, see
“ Engine Oil ” in the Duramax diesel
supplement.
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“ Selecting the Right Engine Oil ”
in this section.
.
Check the engine oil level
regularly and maintain the
proper oil level. See “ Checking
Engine Oil ” and “ When to Add
Engine Oil ” in this section.
.
Change the engine oil at the
appropriate time. See Engine Oil
Life System 0 353 .
.
Always dispose of engine oil
properly. See “ What to Do with
Used Oil ” in this section.