2018 CHEVROLET SILVERADO 1500 wheel

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
320 Driving and Operating
especially important for short box
pickups. Trailer pin box extensions
and sliding fifth-wheel hitch
assemblies can help this condition.
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.
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Instructions about safety chains
may be provided by the hitch
manufacturer or by the trailer
manufacturer. If the trailer is being
towed with a factory-installed step
bumper, safety chains may be
attached to the attaching points on
the bumper; otherwise, safety
chains should be attached to holes
on the trailer hitch platform. Always
leave just enough slack so thecombination can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 900 kg (2,000 lb) must be
equipped with its own brake system,
with brakes working on all axles.
Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State and local regulations may also
require the trailer to have its own
braking system if loaded above a
certain threshold. These
requirements vary from state to
state.
Read and follow the instructions for
the trailer brakes so they are
installed, adjusted, and maintained
properly.
Do not tap into the vehicle's
hydraulic brake system.
Auxiliary Battery
The auxiliary battery provision can
be used to supply electrical power
to additional equipment that may be
added, such as a slide-in camper.
If equipped, this relay will be on the
driver side of the vehicle, next to the
underhood electrical center.
Be sure to follow the proper
installation instructions included with
any electrical equipment that is
installed.
Caution
Leaving electrical equipment on
for extended periods will drain the
battery. Always turn off electrical
equipment when not in use and
do not use equipment that
exceeds the maximum amperage
rating of 30 amps for the auxiliary
battery provision.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
322 Driving and Operating
For vehicles with the fifth 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: Right Stop/Turn
Signal
. Yellow/Gray: Left Stop/Turn
Signal
. Gray/Brown: Taillamps/Parking
Lamps
. White/Green: Back-up Lamps
. Red/Green: Battery Feed .
White: Ground
. Blue: Electric 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 fifth wheel/
gooseneck trailer 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: Right Stop/Turn
Signal
. Yellow/Gray: Left Stop/Turn
Signal .
Gray/Brown: Taillamps/Parking
Lamps
. White/Green: Back-up Lamps
. Red/Green: Battery Feed
. White: Ground
. Blue: Electric Trailer Brake
If the vehicle is equipped with the
heavy-duty trailering option, see
“Heavy-Duty Trailer Wiring Harness
Package” earlier in this section.Electric Brake Control Wiring
Provisions
Wiring provisions for an electric
trailer brake controller are included
with the vehicle as part of the trailer
wiring package. The instrument
panel contains blunt cut wires above
the parking brake assembly for the
electric trailer brake controller.
The harness contains the following
circuits:
.
Blue: Electric Trailer Brakes
. Red/Black or Red/Blue:
Battery Feed
. White/Blue: Brake Apply Signal

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
324 Driving and Operating
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle’s brake
system, and on the type of trailer
brakes detected. This available
power output to the trailer brakes
can be adjusted to a wide range of
trailering situations.
The ITBC system is integrated with
the vehicle’s brake, antilock brake,
and StabiliTrak systems. In trailering
conditions that cause the vehicle’s
antilock brake or StabiliTrak
systems to activate, power sent to
the trailer's brakes will be
automatically adjusted to minimize
trailer wheel lock-up. This does not
imply that the trailer has StabiliTrak. If the vehicle’s brake, antilock brake,
or StabiliTrak systems are not
functioning properly, the ITBC
system may not be fully functional
or may not function at all. Make sure
all of these systems are fully
operational to ensure full
functionality of the ITBC system.
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off will
also turn off the ITBC system. The
ITBC system is fully functional only
when the ignition is in ON/RUN.
{Warning
Connecting a trailer that has an
air brake system may result in
reduced or complete loss of trailer
braking. There may be an
increase in stopping distance or
trailer instability which could
result in personal injury or
damage to the vehicle, trailer,
or other property. Use the ITBC
(Continued)
Warning (Continued)
system only with electric or
electric over hydraulic trailer
brakes.
Trailer Brake Control Panel
1. Manual Trailer Brake Apply Lever
2. Trailer Gain Adjustment Buttons
The ITBC system has a control
panel on the instrument panel to the
left of the steering column. See
Instrument Panel 06. The control

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
326 Driving and Operating
The trailer's and the vehicle's brake
lamps will come on when either
vehicle brakes or manual trailer
brakes are applied.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and must
be adjusted anytime vehicle loading,
trailer loading, or road surface
conditions change.
{Warning
Trailer brakes that are
over-gained or under-gained may
not stop the vehicle and the trailer
as intended and can result in a
crash. Always follow the
instructions to set the Trailer Gain
for the proper trailer stopping
performance.
Use the following to adjust Trailer
Gain for each towing condition: 1. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake Apply
Lever.
Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.
2. Adjust the Trailer Gain, using the Trailer Gain Adjustment
Buttons, to just below the point
of trailer wheel lock-up,
indicated by trailer wheel
squeal or tire smoke when a
trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
3. Readjust Trailer Gain anytime vehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing. Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.
The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
Driving and Operating 327
If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side. If the CHECK TRAILER
WIRING message only
reappears when connecting the
trailer wiring harness to the
vehicle, the electrical fault is on
the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, there is a problem with the
ITBC system. Have the vehicle
serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service. 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
Trailer Sway Control (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 the

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
332 Driving and Operating
(W x (A + W.B.)) /W.B.= Weight the
accessory is adding to the
front axle.
Where:W = Weight of added accessory
A = Distance that the accessory
is in front of the front axle
W.B. = Vehicle Wheelbase
For example, adding a 318 kg
(700 lb) snow plow actually adds
more than 318 kg (700 lb) to the
front axle. Using the formula, if the
snow plow is 122 cm (4 ft) in front of
the front axle and the wheelbase is
305 cm (10 ft), then: W = 318 kg (700 lb)
A = 122 cm (4 ft) W.B. = 305 cm (10 ft)
(W x (A + W.B.)/W.B. =
(318 x (122 + 305))/305 = 445 kg
(980 lb)
This means if the front axle reserve
capacity is more than 445 kg
(980 lb), the snow plow could be
added without exceeding the
front GAWR.
Heavier equipment can be added on
the front of the vehicle if less cargo
or fewer passengers are carried,
or by positioning cargo toward the
rear. This reduces the load on the
front. However, the front GAWR,
rear GAWR, and Gross Vehicle
Weight Rating (GVWR) must never
be exceeded.
{Warning
On some vehicles that have
certain front mounted equipment,
such as a snow plow, it may be
possible to load the front axle to
the front Gross Axle Weight
Rating (GAWR) but not have (Continued)
Warning (Continued)
enough weight on the rear axle to
have proper braking performance.
If the brakes cannot work
properly, the vehice could crash.
Always follow the snow plow
manufacturer or installer's
recommendation for rear ballast
to ensure a proper front and rear
weight distribution ratio.
Maintaining a proper front and
rear weight distribution ratio is
necessary to provide proper
braking performance.
Total vehicle reserve capacity is the
difference between the GVWR and
the weight of the truck with full fuel
and passengers. It is the amount of
weight that can be added to the
vehicle before reaching the GVWR.
Reserve capacity numbers are
intended as a guide when selecting
the amount of equipment or cargo
the truck can carry. If unsure of the
vehicle's front, rear, or total weight,

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
334 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 335
California Proposition65 Warning . . . . . . . . . . . . . . . . . 336
California Perchlorate Materials Requirements . . . . . 336
Accessories and Modifications . . . . . . . . . . . . . . . . 336
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 337
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 337
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 338
Engine Oil . . . . . . . . . . . . . . . . . . . . 343
Engine Oil Life System . . . . . . . 346
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 347
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 350
Manual Transmission Fluid . . . 350
Hydraulic Clutch . . . . . . . . . . . . . . 351
Engine Air Cleaner/Filter . . . . . . 351
Cooling System . . . . . . . . . . . . . . 352
Engine Overheating . . . . . . . . . . 356 Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 358
Engine Fan . . . . . . . . . . . . . . . . . . . 358
Power Steering Fluid (1500 Series) . . . . . . . . . . . . . . . . . . . . . . 359
Power Steering Fluid (2500/ 3500 Series) . . . . . . . . . . . . . . . . 359
Washer Fluid . . . . . . . . . . . . . . . . . 359
Brakes . . . . . . . . . . . . . . . . . . . . . . . 360
Brake Fluid . . . . . . . . . . . . . . . . . . . 361
Battery - North America . . . . . . 362
Four-Wheel Drive . . . . . . . . . . . . . 363
Front Axle . . . . . . . . . . . . . . . . . . . . 364
Rear Axle . . . . . . . . . . . . . . . . . . . . 365
Noise Control System . . . . . . . . 366
Starter Switch Check . . . . . . . . . 367
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 368
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 368
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 368
Wiper Blade Replacement . . . . 369
Windshield Replacement . . . . . 369
Gas Strut(s) . . . . . . . . . . . . . . . . . . 370
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 371
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 371
Halogen Bulbs . . . . . . . . . . . . . . . . 371
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 371
LED Lighting . . . . . . . . . . . . . . . . . 371
Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 372
Fog Lamps . . . . . . . . . . . . . . . . . . . 373
Taillamps (Chassis Cab Models) . . . . . . . . . . . . . . . . . . . . . 373
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 373
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 375
Electrical System
High Voltage Devices andWiring . . . . . . . . . . . . . . . . . . . . . . . 375
Electrical System Overload . . . 375
Fuses and Circuit Breakers . . . 376
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 376
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 380
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 381

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349200) - 2018 - CRC - 2/27/18
Vehicle Care 335
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 384
All-Season Tires . . . . . . . . . . . . . . 384
Winter Tires . . . . . . . . . . . . . . . . . . 385
Low-Profile Tires . . . . . . . . . . . . . 385
All-Terrain Tires . . . . . . . . . . . . . . . 386
Tire Sidewall Labeling . . . . . . . . 386
Tire Designations . . . . . . . . . . . . . 388
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 390
Tire Pressure . . . . . . . . . . . . . . . . . 392
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 394
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 394
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 395
Tire Inspection . . . . . . . . . . . . . . . . 399
Tire Rotation . . . . . . . . . . . . . . . . . 400
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 402
Buying New Tires . . . . . . . . . . . . . 403
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 404
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 405
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 406
Wheel Replacement . . . . . . . . . . 407
Tire Chains . . . . . . . . . . . . . . . . . . . 408 If a Tire Goes Flat . . . . . . . . . . . . 408
Tire Changing . . . . . . . . . . . . . . . . 410
Full-Size Spare Tire . . . . . . . . . . 420
Jump Starting
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 421
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 425
Recreational VehicleTowing . . . . . . . . . . . . . . . . . . . . . . 425
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 430
Interior Care . . . . . . . . . . . . . . . . . . 436
Floor Mats . . . . . . . . . . . . . . . . . . . . 439
General Information
For service and parts needs, visit
your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks: