2015 GMC SIERRA DENALI check transmission fluid

Black plate (13,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-13Caution (Continued)system parts, starting a fire. Too
little fluid could cause the
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)
on page 5-27 .
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
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 on page 10-5 .
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.

Black plate (14,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-14 Vehicle Care 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. 1. Locate the transmission dipstick
at the rear of the engine
compartment, on the passenger
side of the vehicle.
See Engine Compartment
Overview on page 10-5 .
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.

Black plate (15,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-155. 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
on page 13-11 .{ CautionUse 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 on page 11-12 .
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule on
page 11-3 . Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants on page 11-12 .
Engine Air Cleaner/Filter If the vehicle has a diesel engine,
see “ Pickup Models ” under “ Engine
Air Cleaner/Filter ” in the Duramax
diesel supplement for the correct
inspection and replacement
procedures.

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-4 Service and Maintenance .
Visually inspect windshield wiper
blades for wear, cracking,
or contamination. See Exterior
Care on page 10-96 . Replace
worn or damaged wiper blades.
See Wiper Blade Replacement
on page 10-35 ..
Check tire inflation pressures.
See Tire Pressure on
page 10-59 ..
Inspect tire wear. See Tire
Inspection on page 10-65 ..
Visually check for fluid leaks. .
Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter on
page 10-15 ..
Inspect brake system. .
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 on page 10-96 .
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 on page 3-16 . .
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 on page 10-96 ..
Check starter switch. See Starter
Switch Check on page 10-33 ..
Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check on
page 10-34 . .
Check ignition transmission lock.
See Ignition Transmission Lock
Check on page 10-34 . .
Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check on
page 10-34 . .
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. See your
dealer if service is required. .
Inspect sunroof track and seal,
if equipped. See Sunroof on
page 2-22 . .
Verify spare tire key lock
operation and lubricate as
needed. See Tire Changing on
page 10-76 .

Black plate (7,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-7Maintenance 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.
@ @ @Change transfer case fluid, if equipped with
4WD. (4)
@ @ @Extreme Service: Change transfer case fluid,
if equipped with 4WD. (4, 5)
@ @ @ @ @ @Drain and fill engine cooling system. (6)
@Visually inspect accessory drive belts. (7)
@Replace brake fluid. (8)
@ @ @

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-1
AAccessories and
Modifications . . . . . . . . . . . . . . . . . 10-3
Accessory Power . . . . . . . . . . . . . . 9-29
Active Fuel Management ®
. . . . . 9-32
Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . . . 9-88
Adding a Snow Plow or
Similar Equipment . . . . . . . . . . . . 9-88
Additional Information
OnStar ®
. . . . . . . . . . . . . . . . . . . . . . 14-6
Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . . . 11-9
Adjustable Throttle and
Brake Pedal . . . . . . . . . . . . . . . . . . 9-23
Adjustments
Lumbar, Front Seats . . . . . . . . . . . 3-3
Air Cleaner/Filter, Engine . . . . . 10-15
Air Filter, Passenger
Compartment . . . . . . . . . . . . . . . . . 8-5
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 8-4 Airbag System
Check . . . . . . . . . . . . . . . . . . . . . . . . 3-29
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . 3-22
Passenger Sensing
System . . . . . . . . . . . . . . . . . . . . . . 3-24
What Makes an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-22
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . 3-22
When Should an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . 3-20
Where Are the Airbags? . . . . . . 3-18
Airbags
Adding Equipment to the
Vehicle . . . . . . . . . . . . . . . . . . . . . . 3-28
Passenger Status Indicator . . . 5-17
Readiness Light . . . . . . . . . . . . . . 5-16
Servicing Airbag-Equipped
Vehicles . . . . . . . . . . . . . . . . . . . . . 3-28
System Check . . . . . . . . . . . . . . . . 3-17
Alarm
Vehicle Security . . . . . . . . . . . . . . 2-11
All-Season Tires . . . . . . . . . . . . . . 10-51
All-Terrain Tires . . . . . . . . . . . . . . . 10-52 Antilock Brake
System (ABS) . . . . . . . . . . . . . . . . 9-46
Warning Light . . . . . . . . . . . . . . . . . 5-21
Appearance Care
Exterior . . . . . . . . . . . . . . . . . . . . . 10-96
Interior . . . . . . . . . . . . . . . . . . . . . 10-101
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . 13-5
Assistance Systems for
Driving . . . . . . . . . . . . . . . . . . . . . . . 9-59
Assistance Systems for
Parking and Backing . . . . . . . . . 9-56
Automatic
Dimming Mirrors . . . . . . . . . . . . . . 2-17
Door Locks . . . . . . . . . . . . . . . . . . . . 2-9
Headlamp System . . . . . . . . . . . . . 6-3
Transmission . . . . . . . . . . . . . . . . . 9-33
Transmission Fluid . . 10-12, 10-15
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . 9-36
Shift Lock Control
Function Check . . . . . . . . . . . 10-34
Auxiliary
Roof Mounted Lamp . . . . . . . . . . . 6-5
Axle, Front . . . . . . . . . . . . . . . . . . . . 10-30
Axle, Rear . . . . . . . . . . . . . . . . . . . . 10-31

Black plate (2,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
i-2 INDEX
BBattery . . . . . . . . . . . . . . . . . . . . . . . 10-29
Jump Starting . . . . . . . . . . . . . . . 10-87
Load Management . . . . . . . . . . . . . 6-8
Power Protection . . . . . . . . . . . . . . 6-9
Voltage and Charging
Messages . . . . . . . . . . . . . . . . . . . 5-31
Blade Replacement, Wiper . . . 10-35
Blind Spot Mirrors . . . . . . . . . . . . . 2-17
Brake
Pedal and Adjustable
Throttle . . . . . . . . . . . . . . . . . . . . . . 9-23
System Warning Light . . . . . . . . 5-21
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 10-26
Antilock . . . . . . . . . . . . . . . . . . . . . . . 9-46
Assist . . . . . . . . . . . . . . . . . . . . . . . . . 9-48
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 10-27
Parking . . . . . . . . . . . . . . . . . . . . . . . 9-47
System Messages . . . . . . . . . . . . 5-32
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Break-In, New Vehicle . . . . . . . . . 9-23 Bulb Replacement . . . . . . . . . . . . 10-40
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . 10-39
Halogen Bulbs . . . . . . . . . . . . . . 10-36
Headlamp Aiming . . . . . . . . . . . 10-36
Headlamps . . . . . . . . . . . . . . . . . 10-36
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-36
Taillamps, Turn Signal,
Stoplamps, and
Back-up Lamps . . . . . . . . . . . 10-37
Buying New Tires . . . . . . . . . . . . . 10-69
C Calibration . . . . . . . . . . . . . . . . . . . . . . 5-4
California
Fuel Requirements . . . . . . . . . . . 9-64
Perchlorate Materials
Requirements . . . . . . . . . . . . . . . 10-3
Warning . . . . . . . . . . . . . . . . . . . . . . 10-2
Canadian Vehicle Owners . . . . . . . . iii
Capacities and
Specifications . . . . . . . . . . . . . . . . 12-2 Carbon Monoxide
Engine Exhaust . . . . . . . . . . . . . . . 9-32
Tailgate . . . . . . . . . . . . . . . . . . . . . . . 2-10
Winter Driving . . . . . . . . . . . . . . . . 9-12
Cargo
Tie-Downs . . . . . . . . . . . . . . . . . . . . . 4-3
Cargo Lamp . . . . . . . . . . . . . . . . . . . . 6-6
Cautions, Danger, and
Warnings . . . . . . . . . . . . . . . . . . . . . . . . iv
Center Console Storage . . . . . . . . 4-2
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 10-39
Chains, Tire . . . . . . . . . . . . . . . . . . 10-74
Charging System Light . . . . . . . . 5-18
Check
Engine Light . . . . . . . . . . . . . . . . . . 5-18
Ignition
Transmission Lock . . . . . . . . 10-34

Black plate (11,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-11Service . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Accessories and
Modifications . . . . . . . . . . . . . . . . 10-3
Doing Your Own Work . . . . . . . . 10-3
Engine Soon Light . . . . . . . . . . . . 5-18
Maintenance Records . . . . . . .11-16
Maintenance, General
Information . . . . . . . . . . . . . . . . . . 11-1
Parts Identification Label . . . . . 12-1
Publications Ordering
Information . . . . . . . . . . . . . . . . .13-11
Scheduling Appointments . . . . . 13-7
Services
Special Application . . . . . . . . . . . 11-8
Servicing the Airbag . . . . . . . . . . . 3-28
Shift Lock Control Function
Check, Automatic
Transmission . . . . . . . . . . . . . . . . 10-34
Shifting
Into Park . . . . . . . . . . . . . . . . . . . . . . 9-30
Out of Park . . . . . . . . . . . . . . . . . . . 9-31
Signals, Turn and
Lane-Change . . . . . . . . . . . . . . . . . 6-4
Snow Plow . . . . . . . . . . . . . . . . . . . . 9-88
Special Application Services . . . 11-8 Specifications and
Capacities . . . . . . . . . . . . . . . . . . . . 12-2
Speedometer . . . . . . . . . . . . . . . . . . 5-11
StabiliTrak
OFF Light . . . . . . . . . . . . . . . . . . . . . 5-23
Start Assist, Hills . . . . . . . . . . . . . . 9-48
Start Vehicle, Remote . . . . . . . . . . 2-7
Starter Switch Check . . . . . . . . . 10-33
Starting the Engine . . . . . . . . . . . . 9-26
Steering . . . . . . . . . . . . . . . . . . . . . . . . 9-4
Fluid, Power . . . . . . . . . . . . . . . . 10-24
Heated Wheel . . . . . . . . . . . . . . . . . 5-3
Wheel Adjustment . . . . . . . . . . . . . 5-2
Wheel Controls . . . . . . . . . . . . . . . . 5-2
Steering System Messages . . . . 5-38
Stoplamps and Back-up Lamps
Bulb Replacement . . . . . . . . . . 10-37
Storage Areas
Center Console . . . . . . . . . . . . . . . . 4-2
Floor Console . . . . . . . . . . . . . . . . . 4-3
Glove Box . . . . . . . . . . . . . . . . . . . . . 4-1
Instrument Panel . . . . . . . . . . . . . . 4-1
Sunglasses . . . . . . . . . . . . . . . . . . . . 4-2
Storage Compartments . . . . . . . . . 4-1
Stuck Vehicle . . . . . . . . . . . . . . . . . . 9-14
Sun Visors . . . . . . . . . . . . . . . . . . . . . 2-22 Sunglass Storage . . . . . . . . . . . . . . . 4-2
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . iv
System
Forward Collision
Alert (FCA) . . . . . . . . . . . . . . . . . . 9-59
Infotainment . . . . . . . . . . . . 7-1, 13-15
Noise Control . . . . . . . . . . . . . . . 10-32
Systems
Driver Assistance . . . . . . . . . . . . . 9-55
T Tachometer . . . . . . . . . . . . . . . . . . . . 5-11
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Taillamps
Bulb Replacement . . . . . . . . . . 10-37
Text Telephone (TTY) Users . . . 13-4
Theft-Deterrent Systems . . . . . . . 2-13
Immobilizer . . . . . . . . . . . . . . . . . . . 2-12
Throttle, Adjustable . . . . . . . . . . . . 9-23
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 10-50
All-Season . . . . . . . . . . . . . . . . . . 10-51
All-Terrain . . . . . . . . . . . . . . . . . . 10-52
Buying New Tires . . . . . . . . . . . 10-69
Chains . . . . . . . . . . . . . . . . . . . . . . 10-74