line GMC SIERRA DENALI 2024 Service Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 273
The use of E85 or FlexFuel is encouraged
when the vehicle is designed to use it. E85
or FlexFuel is made from renewable sources.
To help locate fuel stations that carry E85 or
FlexFuel, the U.S. Department of Energy has
an alternative fuel website. See
www.afdc.energy.gov/afdc/locator/stations.
E85 or FlexFuel should meet ASTM
Specification D 5798 or CAN/CGSB–3.512 in
Canada. Do not use the fuel if the ethanol
content is greater than 85%. Fuel mixtures
that do not meet ASTM or CGSB
specifications can affect driveability and
could cause the malfunction indicator lamp
to come on.
The starting characteristics of E85 or FlexFuel
make it unsuitable for use when
temperatures fall below−18 °C (0 °F). Use
gasoline or add gasoline to the E85 or
FlexFuel.
Because E85 or FlexFuel has less energy per
liter (gallon) than gasoline, the vehicle will
need to be refilled more often. See Filling
the Tank (Chassis Cab and Box Delete
Models) 0275 or
Filling the Tank (Pickup Models) 0273. The only GM approved aftermarket additive
is ACDelco Fuel System Treatment
Plus-FlexFuel. Follow the instructions on the
bottle for proper use. This product is
available at your GM dealer.
Caution
Some additives are not compatible with
E85 or FlexFuel and can harm the
vehicle's fuel system. Use only additives
approved by GM for E85 or FlexFuel
vehicles. Damage caused by unapproved
additives would not be covered by the
vehicle warranty.
Caution
Do not use fuel containing methanol.
It can corrode metal parts in the fuel
system and also damage plastic and
rubber parts. That damage would not be
covered under the vehicle warranty.
To help keep the engine running efficiently,
fill the tank with gasoline, up to E15, after
filling the tank with E85 one or two times.
Filling the Tank (Pickup Models)
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
An arrow on the fuel gauge indicates which
side of the vehicle the fuel door is on. See
Fuel Gauge 0116.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
(Continued)

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 275
Filling the Tank (Chassis Cab and
Box Delete Models)
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
An arrow on the fuel gauge indicates which
side of the vehicle the fuel fill is on. See
Fuel Gauge0116.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
(Continued)
Warning (Continued)
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fuel cap is
opened too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Open the
fuel cap slowly and wait for any hiss
noise to stop, then unscrew the cap all
the way.
Turn the fuel cap counterclockwise to
remove. Fully insert and latch the fill nozzle,
begin fueling. For models with dual fuel
tanks, the fuel gauge shows an average of
both tanks. When refueling, refuel the
primary front tank first, then add fuel to the
auxiliary rear tank.
{Warning
Overfilling the fuel tank by more than
three clicks of a standard fill nozzle may
cause:
.Vehicle performance issues, including
engine stalling and damage to the fuel
system.
.Fuel spills.
.Under certain conditions, fuel fires.
Be careful not to spill fuel. Wait five seconds
after you have finished pumping before
removing the fill nozzle. Clean fuel from
painted surfaces as soon as possible. See
Exterior Care 0383. Reinstall the cap by
turning it clockwise until it clicks.
{Warning
If a fire starts while you are refueling, do
not remove the fill nozzle. Shut off the
flow of fuel by shutting off the pump or
by notifying the station attendant. Leave
the area immediately.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 285
Gooseneck Hitch
A gooseneck hitch is designed to be coupled
to a special hitch leveraging a hitch ball, and
is mounted over the rear axle in the
truck bed.
Fifth-Wheel Hitch
A fifth-wheel hitch is mounted over the rear
axle in the truck bed, and leverages a
hinged plate—the same type of hitch
leveraged by semi trucks. Generally,
fifth-wheel hitches accommodate large
trailers with as many as one, two, or three
axles.
Always use the correct hitch equipment for
your vehicle. Crosswinds, large trucks going
by, and rough roads can affect the trailer
and the hitch. Proper hitch equipment for your vehicle
helps maintain control of the vehicle-trailer
combination. Many trailers can be towed
using a weight-carrying hitch which has a
coupler latched to the hitch ball, or a tow
eye latched to a pintle hook. Other trailers
may require a weight-distributing hitch that
uses spring bars to distribute the trailer
tongue weight between your vehicle and
trailer axles. Fifth-wheel and gooseneck
hitches may also be used. See
“Maximum
Trailer Tongue Weight” underTrailer Towing
0 280 for weight limits with various hitch
types.
Avoid sharp turns when using a step-bumper
hitch to prevent damage. Make wider turns
to prevent contact between your trailer and
your bumper. Consider using mechanical sway controls
with any trailer. Ask a trailering professional
about sway controls or refer to the trailer
manufacturer's recommendations and
instructions.
Weight-Distributing Hitch and
Adjustment
A weight-distributing hitch may be useful
with some trailers. Use the following
guidelines to determine if a
weight-distributing hitch should be used.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 287
MeasurementHeight Example 2500/3500 (mm)
H1 1 040
H2 1 080
H2−H1 40
(H2−H1)/4 10
H2−[(H2−H1)/4] 1 070
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to support
loads while towing a trailer. SeeTires
0 345 for instructions on proper tire
inflation.
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
Gross Axle Weight Rating (GAWR) or Gross
Vehicle Weight Rating (GVWR). Fifth-wheel
or gooseneck kingpin weight should be
15 –25% of the trailer weight up to the maximum amount specified on the Trailering
Information Label. See
“Trailer Weight"
under Trailer Towing 0280.
The hitch should be in the pickup bed so
that its centerline is over or near 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 pickups. Trailer pin box extensions
and sliding fifth-wheel hitch assemblies may
be used. There should be at least 15 cm
(6 in) of clearance between the top of the
pickup box and the bottom of the trailer
shelf that extends over the box.
Attach the hitch to the tow vehicle frame
rails. Do not use the pickup box for support.
Two Inch Adapter Sleeve and
Retainer Pin
The 2500/3500 series vehicles are equipped
with a 2-1/2” square receiver. An adapter is
provided to allow the use of a 2” draw bar,
along with a hitch retainer pin, and
retainer clip.
Safety Chains
Always attach safety chains between the
vehicle and the trailer. Instructions about
safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer.
If the trailer being towed weighs up to
2 271 kg (5,000 lb) with a factory-installed
step bumper, safety chains may be attached

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 301
next time the vehicle is turned on (if trailer
was disconnected while vehicle is off). Check
your trailer connection if needed.
Connection Problem
If any of the trailer connections are lost, a
message about the connection issue appears
on the DIC. The infotainment screen will also
show the connection issue in the Lights
Status view.
Connection Trailer Lighting Faults Detected
The Trailering App monitors for electrical
faults on the trailer lights. A message about
the lighting issue appears on the DIC. The
infotainment screen will also show the
lighting issue in the Lights Status view.
Repair your trailer lights if needed. A trailer
lighting issue is not covered by your GM
warranty.
The Running Lights connection may not
detect partial outages. Activate the light test
to check all trailer lamps. See“Light Test”
following. Light Test
Touch Start Light Test to cycle the trailer
lights on and off to determine if they are
working. The test follows this sequence:
1. The running lights turn on first and remain on throughout the sequence.
2. The brake lights turn on for about two seconds.
3. The left turn signal light flashes three times.
4. The right turn signal light flashes three times.
5. The reverse lights turn on for about two seconds.
6. Steps 2-5 repeat for approximately one minute and 45 seconds, or until the
test deactivates.
Touch Stop to stop the test. The test will
automatically end after one minute and
45 seconds.
The sequence also deactivates when any of
the following occur:
.The vehicle is turned off.
.The transmission is shifted out of
P (Park).
.The brake pedal is pressed.
.The turn signal is activated.
.The hazard warning lights are activated.
Tires
Tire Pressure and Temperature
If the TTPMS sensor-to-vehicle learn process
was completed, the status view will display
the current tire pressure and temperature of
the trailer tires related to the active Trailer
Profile. If a tire’s pressure is low or high, the
color of the pressure value will be amber.
If a sensor malfunctions, the values are
dashed lines. If the screen displays “Service
Tire Pressure Monitoring System,” the
vehicle needs to be taken to a dealer for
service.
Touch to set up the TTPMS for the Trailer
Profile. See “Trailer Tire Pressure Setup”
previously in this section for details on the
setup. Also, touch Sensor Setup if the trailer

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
306 Driving and Operating
If Tow/Haul Mode is off and this setting is
on for a Trailer Profile, each time the vehicle
is turned on, a reminder will appear in the
DIC to turn on Tow/Haul Mode when the
Trailer Profile is active.
If Tow/Haul Mode is on and this setting is
on for a Trailer Profile, the reminder will not
appear when the Trailer Profile is active.
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) 0122.
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 073 and
Adding Equipment to the Airbag-Equipped
Vehicle 073.
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 72 km/h (45 mph) with a
snow plow mounted to the vehicle. The
vehicle could overheat and be damaged.
Before installing a snow plow on the vehicle,
follow these guidelines:
Caution
If the vehicle does not have the snow
plow prep package, RPO VYU, adding a
plow can damage the vehicle, and the
repairs would not be covered by the
vehicle warranty. Unless the vehicle was
built to carry a snow plow, do not add
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.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
314 Vehicle Care
1. Remote Negative (–) Location. SeeJump
Starting - North America 0376.
2. Positive (+) Terminal (Under Cover). See Jump Starting - North America 0376.
3. Battery - North America 0327.
4. Engine Air Cleaner/Filter 0318.
5. Engine Oil Dipstick. See “Checking Engine
Oil” under Engine Oil 0314.
6. Engine Cooling Fan (Out of View). See Cooling System 0319.
7. Power Steering Fluid Reservoir. See Power Steering Fluid 0323.
8. Engine Oil Fill Cap. See “When to Add
Engine Oil” underEngine Oil 0314.
9. Auxiliary Battery. Battery - North
America 0327.
10. Brake Fluid Reservoir. See Brake Fluid
0 326.
11. Engine Compartment Fuse Block 0337.
12. Coolant Surge Tank and Pressure Cap. SeeCooling System 0319.
13. Windshield Washer Fluid Reservoir. See “Adding Washer Fluid” underWasher
Fluid 0324.
If the vehicle has a diesel engine, see the
Duramax diesel 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. SeeEngine Oil Life System 0316.
.Always dispose of engine oil properly. See
“What to Do with Used Oil” in this
section.
Checking Engine Oil
Check the engine oil level regularly, every
650 km (400 mi), especially prior to a long
trip. The engine oil dipstick handle is a loop.
See Engine Compartment Overview 0313 for
the location.
{Warning
The engine oil dipstick handle may be
hot; it could burn you. Use a towel or
glove to touch the dipstick handle.
If a low oil Driver Information Center (DIC)
message displays, check the oil level.
Follow these guidelines:
.To get an accurate reading, park the
vehicle on level ground. Check the engine
oil level after the engine has been off for
at least two hours. Checking the engine
oil level on steep grades or too soon after
engine shutoff can result in incorrect
readings. Accuracy improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the
dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
328 Vehicle Care
Extended Storage: Remove the black,
negative (−) cable from the battery or use a
battery trickle charger.
Negative Battery Cable Disconnection
{Warning
Before disconnecting the negative battery
cable, turn off all features, turn the
ignition off, and remove the key,
if equipped, from the vehicle. If this is
not done, you or others could be injured,
and the vehicle could be damaged.
Caution
If the battery is disconnected with the
ignition on or the vehicle in Retained
Accessory Power (RAP), the OnStar
back-up battery will be permanently
discharged and will need to be replaced.
1. Make sure the lamps, features, and accessories are turned off.
2. Turn the vehicle off and remove the key, if equipped.
1. Loosen the negative battery cable nut (1).
2. Remove the negative battery cableclamp (2) from the negative battery post.
3. Cover the negative battery cable clamp, and negative battery post with a
non-conductive material to prevent any
contact with the negative battery cable.
Negative Battery Cable Reconnection
Caution
When reconnecting the battery:
.Use the original nut from the vehicle
to secure the negative battery cable.
Do not use a different nut. If you
need a replacement nut, see your
dealer.
.Tighten the nut with a hand tool. Do
not use an impact wrench or power
tools to tighten the nut.
The vehicle could be damaged if these
guidelines are not followed.
Caution
Do not use paints, lubricants, or corrosion
inhibitors on the nut that secures the
negative battery cable to the vehicle. This
could damage the vehicle.
1. Install the negative battery cable clamp to the negative battery post.
2. Tighten the negative battery cable nut.
3. Turn the vehicle on.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Vehicle Care 339
FusesUsage
6 –
7 ELM 4 –Electronic
Lighting Module 4
8 –
9 –
10 ELM 6 –Electronic
Lighting Module 6
11 BCM 3 –Body Control
Module 3
12 Rear Window Defogger
13 Washer Front
14 –
15 –
16 –
17 IECL 1
19 DC/AC Inverter
20 IECR 2 (LD)/EBCM2 (HD) 21 –
22 IECL 2
24 Fuel Heater (DSL) Fuses
Usage
25 EBCM 1 –Electronic
Brake Control Module 1
26 –
27 Horn
28 Parking Lamp Mirror/ Grill (LD)/Parking Lamp
Left (HD)
29 Parking Lamp Right (HD)
30 ELM 3 –Electronic
Lighting Module 3
31 ELM 1 –Electronic
Lighting Module 1
32 –
33 Not R/C
34 Radars (LD) 37 MISC IP Headliner Ignition
38 Seat Fan Ignition
39 Trailer Ignition Module
40 Misc Ignition 41 Trailer Parking Lamp Fuses
Usage
42 Tail Lamp Left (HD)
44 DEFC/ICCM Ignition (LD/ HD)/FTZM Ignition (HD)
45 Secondary Axle Motor
46 Engine Control Module Ignition
47 –
48 –
49 Transmission Auxiliary Oil Pump (LD)
50 A/C Clutch 51 Transfer Case Control Module
52 Front Wiper
53 Center High-Mounted Stop Lamp
54 Tail Lamp Right (HD) 55 Trailer Back-up Lamp
56 SADS (LD)/Fuel Tank Zone Module 2 (HD)
57 TTPM/SBZA
58 Starter Motor (LD)

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
346 Vehicle Care
provide adequate performance for most
winter driving conditions, but they may not
offer the same level of traction or
performance as winter tires on snow or
ice-covered roads. SeeWinter Tires0346.
Winter Tires
This vehicle was not originally equipped
with winter tires. Winter tires are designed
for increased traction on snow and
ice-covered roads. Consider installing winter
tires on the vehicle if frequent driving on ice
or snow covered roads is expected. See your
dealer for details regarding winter tire
availability and proper tire selection. Also,
see Buying New Tires 0360.
With winter tires, there may be decreased
dry road traction, increased road noise, and
shorter tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
.Use tires of the same brand and tread
type on all four wheel positions.
.Use only radial ply tires of the same size,
load range, and speed rating as the
original equipment tires. Winter tires with the same speed rating as
the original equipment tires may not be
available for H, V, W, Y, and ZR speed rated
tires. If winter tires with a lower speed
rating are chosen, never exceed the tire's
maximum speed capability.
All-Terrain Tires
This vehicle may have all-terrain or
mud-terrain tires. These tires provide good
performance on most road surfaces, weather
conditions, and for off-road driving. See
Off-Road Driving
0203.
The tread pattern on these tires may wear
more unevenly than other tires. Consider
rotating the tires more frequently than at
12 000 km (7,500 mi) intervals if irregular
wear is noted when the tires are inspected.
See Tire Inspection 0356.
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The example
shows a typical light truck tire sidewall.
Light Truck (LT-Metric) Tire
(1) Tire Size:The tire size code is a
combination of letters and numbers
used to define a particular tire's width,
height, aspect ratio, construction type,
and service description. See the “Tire
Size” illustration later in this section for
more detail.
(2) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires
designed to GM's specific tire
performance criteria have a TPC
specification code molded onto the
sidewall. GM's TPC specifications meet
or exceed all federal safety guidelines.