
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
354 Vehicle Care How to Reset the Engine Oil
Life System Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To
reset the engine oil life system:
1. Display the OIL LIFE
REMAINING on the DIC. If the
vehicle does not have DIC
buttons, the vehicle must be in
P (Park) to access this display.
See Driver Information Center
(DIC) (Uplevel and Denali
Cluster) 0 160 or Driver
Information Center (DIC) (Base
Level Cluster) 0 158 .
2. Press and hold
V , or the trip
odometer reset stem if the
vehicle does not have DIC
buttons, for several seconds.
The oil life will change
to 100%. The oil life system can also be reset
as follows:
1. Display the OIL LIFE
REMAINING on the DIC.
See Driver Information Center
(DIC) (Uplevel and Denali
Cluster) 0 160 or Driver
Information Center (DIC) (Base
Level Cluster) 0 158 .
2. Fully press the accelerator
pedal slowly three times within
five seconds.
3. Display the OIL LIFE
REMAINING on the DIC. If the
display shows 100%, the
system is reset.
If the vehicle has a CHANGE
ENGINE OIL SOON message and it
comes back on when the vehicle is
started and/or the OIL LIFE
REMAINING is near 0%, the engine
oil life system has not been reset.
Repeat the procedure. Automatic Transmission
Fluid (6-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. If a small leak is
suspected, then use the following
checking procedures to check the
fluid level. However, if there is a
large leak, then it may be necessary
to have the vehicle towed to a
dealer service department and have
it repaired before driving the vehicle
further.
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
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 355Caution (Continued)automatic transmission fluid listed
in Recommended Fluids and
Lubricants 0 456 .
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 448 . Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0 456 .
How to Check Automatic
Transmission Fluid
Caution
Too much or too little fluid can
damage the transmission. Too
much can mean that some of the
fluid could come out and fall on
hot engine parts or exhaust
system parts, starting a fire. Too
little fluid could cause the
(Continued) Caution (Continued) transmission to overheat. Be sure
to get an accurate reading if
checking the transmission fluid.
Before checking the fluid level,
prepare the vehicle:
1. Start the engine and park the
vehicle on a level surface.
Keep the engine running.
2. Apply the parking brake and
place the shift lever in P (Park).
3. With your foot on the brake
pedal, move the shift lever
through each gear range,
pausing for about
three seconds in each range.
Then, move the shift lever back
to P (Park).
4. Allow the engine to idle (500 –
800 rpm) for at least
one minute. Slowly release the
brake pedal. 5. Keep the engine running and
check the transmission fluid
temperature on the Driver
Information Center (DIC).
See Driver Information Center
(DIC) (Uplevel and Denali
Cluster) 0 160 or Driver
Information Center (DIC) (Base
Level Cluster) 0 158 .
6. Using the transmission fluid
temperature reading, determine
and perform the appropriate
check procedure. If the
transmission fluid temperature
reading is not within the
required temperature ranges,
allow the vehicle to cool,
or operate the vehicle until the
appropriate transmission fluid
temperature is reached.
Cold Check Procedure
Use this procedure only as a
reference to determine if the
transmission has enough fluid to be
operated safely until a hot check
procedure can be made. The hot
check procedure is the most
accurate method to check the fluid
level. Perform the hot check

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
356 Vehicle Care procedure at the first opportunity.
Use this cold check procedure to
check fluid level when the
transmission temperature is
between 27 °C and 32 °C (80 °F and
90 °F).
1. Locate the transmission
dipstick at the rear of the
engine compartment, on the
passenger side of the vehicle.
See Engine Compartment
Overview 0 345 .
2. Flip the handle up, then pull out
the dipstick and wipe it with a
clean rag or paper towel.
3. Install the dipstick by pushing it
back in all the way; wait
three seconds, and then pull it
back out again. 4. Check both sides of the
dipstick and read the lower
level. Repeat the check
procedure to verify the reading.
5. If the fluid level is below the
COLD check band, add only
enough fluid as necessary to
bring the level into the COLD
band. It does not take much
fluid, generally less than 0.5 L
(1 pt). Do not overfill.
6. Perform a hot check at the first
opportunity after the
transmission reaches a normal
operating temperature between
71 °C to 93 °C (160 °F to
200 °F). 7. If the fluid level is in the
acceptable range, push the
dipstick back in all the way,
then flip the handle down to
lock the dipstick in place.
Hot Check Procedure
Use this procedure to check the
transmission fluid level when the
transmission fluid temperature is
between 71 °C and 93 °C (160 °F
and 200 °F).
The hot check is the most accurate
method to check the fluid level. The
hot check should be performed at
the first opportunity in order to verify
the cold check. The fluid level rises
as fluid temperature increases, so it
is important to ensure the
transmission temperature is within
range.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 3571. Locate the transmission
dipstick at the rear of the
engine compartment, on the
passenger side of the vehicle.
See Engine Compartment
Overview 0 345 .
2. Flip the handle up, then pull out
the dipstick and wipe it with a
clean rag or paper towel.
3. Install the dipstick by pushing it
back in all the way; wait
three seconds, and then pull it
back out again.
4. Check both sides of the
dipstick and read the lower
level. Repeat the check
procedure to verify the reading. 5. Safe operating level is within
the HOT cross hatch band on
the dipstick. If the fluid level is
not within the HOT band, and
the transmission temperature is
between 71 °C and 93 °C
(160 °F and 200 °F), add or
drain fluid as necessary to
bring the level into the HOT
band. If the fluid level is low,
add only enough fluid to bring
the level into the HOT band.
It does not take much fluid,
generally less than 0.5 L (1 pt).
Do not overfill.
6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way,
then flip the handle down to
lock the dipstick in place.
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 the
service manual. See Service
Publications Ordering Information
0 474 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 365Caution (Continued)attempting any repair. Repair the
cause of coolant loss, change the
oil, and reset the oil life system.
See Engine Oil 0 350 .
Engine Fan If the vehicle has a clutched engine
cooling fan, when the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high
outside temperatures, the fan speed
increases as the clutch more fully
engages, so an increase in fan
noise may be heard. This is normal
and should not be mistaken as the
transmission slipping or making
extra shifts. It is merely the cooling
system functioning properly. The fan will slow down when additional
cooling is not required and the
clutch disengages.
This fan noise may also be heard
when starting the engine. It will go
away as the fan clutch partially
disengages.
If the vehicle has electric cooling
fan(s), the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned. off. This is normal and no
service is required. Power Steering Fluid
(1500 Series) The vehicle has electric power
steering and does not use power
steering fluid.
Power Steering Fluid
(2500/3500 Series)
See Engine Compartment Overview
0 345 for reservoir location.
When to Check Power Steering
Fluid It is not necessary to regularly
check power steering fluid unless
there is a leak suspected in the
system or an unusual noise is
heard. A fluid loss in this system
could indicate a problem. Have the
system inspected and repaired.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Service and Maintenance 449.
Check tire inflation pressures.
See Tire Pressure 0 397 .
.
Inspect tire wear. See Tire
Inspection 0 404 .
.
Visually check for fluid leaks.
.
Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter
0 358 .
.
Inspect brake system. See
Exterior Care 0 435 .
.
Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear
at least once a year. See
Exterior Care 0 435 . Lubricate
the suspension and steering
components at least every other
oil change. (If equipped with
grease fittings)
.
Check restraint system
components. See Safety System
Check 0 75 . .
Visually inspect fuel system for
damage or leaks.
.
Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts.
.
Lubricate body components. See
Exterior Care 0 435 .
.
Check starter switch. See Starter
Switch Check 0 374 .
.
Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check
0 374 .
.
Check ignition transmission lock.
See Ignition Transmission Lock
Check 0 374 .
.
Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check
0 375 . .
Check accelerator pedal for
damage, high effort, or binding.
Replace if needed.
.
Visually inspect gas strut for
signs of wear, cracks, or other
damage. Check the hold open
ability of the strut. If the hold
open ability is low, service the
gas strut. See Gas Strut(s)
0 376 .
.
Inspect sunroof track and seal,
if equipped. See Sunroof 0 55 .
.
Verify spare tire key lock
operation and lubricate as
needed. See Tire Changing
0 415 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
452 Service and Maintenance Maintenance Schedule
Additional Required
Services - Severe
12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 miRotate tires and perform Required Services.
Check engine oil level and oil life percentage.
Change engine oil and filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @Replace passenger compartment air filter. (1)
@ @ @ @ @ @Inspect evaporative control system. (2)
@ @ @Replace engine air cleaner filter. (3)
@ @ @Replace spark plugs. Inspect spark plug wires.
@Change automatic transmission fluid and filter.
@ @ @For GVW under 3 900 kg (8,600 lb), change
transfer case fluid, if equipped with 4WD. (4)
@ @ @For GVW over 3 900 kg (8,600 lb), change
transfer case fluid, if equipped with 4WD. (4)
@ @ @ @ @ @Drain and fill engine cooling system. (5)
@Visually inspect accessory drive belts. (6)
@Replace brake fluid. (7)
Footnotes — Maintenance
Schedule Additional Required
Services — Severe
(1) Or every two years, whichever
comes first. More frequent
replacement may be needed if the vehicle is driven in areas with heavy
traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter
replacement may also be needed if
you notice reduced airflow, windows fogging up, or odors. Your local GM
Service location can help you
determine when it is the right time to
replace your filter.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
492 Index Antilock Brake System
(ABS) (cont'd)
Warning Light . . . . . . . . . . . . . . . . . 152
Appearance Care
Exterior . . . . . . . . . . . . . . . . . . . . . . . 435
Interior . . . . . . . . . . . . . . . . . . . . . . . . 441
Apple CarPlay and
Android Auto . . . . . . . . . . . . . . . . . . 217
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . . 469
Assistance Systems for
Driving . . . . . . . . . . . . . . . . . . . . . . . . 292
Assistance Systems for
Parking and Backing . . . . . . . . . . 289
Audio
Bluetooth . . . . . . . . . . . . . . . . . . . . . 204
Theft-Deterrent Feature . . . . . . . 187
Audio Players
CD . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Automatic
Dimming Mirrors . . . . . . . . . . . . . . . . 50
Door Locks . . . . . . . . . . . . . . . . . . . . . 41
Forward Braking . . . . . . . . . . . . . . 294
Headlamp System . . . . . . . . . . . . 179
Transmission . . . . . . . . . . . . . . . . . 265
Transmission Fluid . . . . . . 354, 357
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . 268 Automatic Transmission (cont'd)
Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Auxiliary
Roof Mounted Lamp . . . . . . . . . . 182
Auxiliary Jack . . . . . . . . . . . . . . . . . . . 203
Avoiding Untrusted Media
Devices . . . . . . . . . . . . . . . . . . . . . . . 195
Axle, Front . . . . . . . . . . . . . . . . . . . . . . 370
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . 371
B Battery
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . 185
Load Management . . . . . . . . . . . . 184
Power Protection . . . . . . . . . . . . . 185
Battery - North America . . . . 369, 426
Blade Replacement, Wiper . . . . . 375
Blind Spot Mirrors . . . . . . . . . . . . . . . 50
Bluetooth
Overview . . . . . . . . . . . . . . . . 211, 213
Bluetooth Audio . . . . . . . . . . . . . . . . 204
Brake
Pedal and Adjustable
Throttle . . . . . . . . . . . . . . . . . . . . . . 256
System Warning Light . . . . . . . . 152
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . 367 Brakes (cont'd)
Antilock . . . . . . . . . . . . . . . . . . . . . . . 280
Assist . . . . . . . . . . . . . . . . . . . . . . . . . 281
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 368
Parking . . . . . . . . . . . . . . . . . . . . . . . 281
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 236
Automatic Forward . . . . . . . . . . . 294
Break-In, New Vehicle . . . . . . . . . . 255
Bulb Replacement
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 380
Halogen Bulbs . . . . . . . . . . . . . . . . 378
Headlamp Aiming . . . . . . . . . . . . . 377
Headlamps . . . . . . . . . . . . . . . . . . . 378
High Intensity Discharge
(HID) Lighting . . . . . . . . . . . . . . . 378
Taillamps, Turn Signal,
Stoplamps, and Back-up
Lamps . . . . . . . . . . . . . . . . . . . . . . 378
Buying New Tires . . . . . . . . . . . . . . . 408
C Calibration . . . . . . . . . . . . . . . . . . . . . . 131
California
Fuel Requirements . . . . . . . . . . . 300