2021 CHEVROLET SUBURBAN power steering

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
236 Driving and Operating
hills or mountain grades, when towing,
or when hauling heavy loads. SeeDriver
Mode Control 0245 to activate Tow/
Haul Mode.
Tow/Haul Mode Grade Braking
Tow/Haul Mode Grade Braking is only
enabled while the Tow/Haul Mode is
selected and the vehicle is not in the Range
Selection Mode. See Manual Mode0235.
Tow/Haul Mode Grade Braking assists in
maintaining desired vehicle speeds when
driving on downhill grades by using the
engine and transmission to slow the vehicle.
See Towing Equipment 0287.
Drive Systems
Four-Wheel Drive
If equipped, four-wheel drive engages the
front axle for extra traction.
Read the appropriate section for transfer
case operation before using.
Caution
Do not drive on clean, dry pavement in 4
mand 4n(if equipped) for an extended
period of time. These conditions may
cause premature wear on the vehicle’s
powertrain.
Driving on clean, dry pavement in 4
mor 4
nmay:
.Cause a vibration to be felt in the
steering system.
.Cause tires to wear faster.
{Warning
If equipped with four-wheel drive, the
vehicle will be free to roll if the transfer
case is in N (Neutral), even when the
transmission is in P (Park). You or
someone else could be seriously injured.
Be sure the transfer case is in a drive
gear —2
m, 4m, or 4n—or set the
parking brake before placing the transfer
case in N (Neutral). See Shifting Into Park
0 230.
Caution
Extended high-speed operation in 4n
may damage or shorten the life of the
drivetrain.
An engagement noise and bump is normal
when shifting between 4
nand 4mor
N (Neutral), with the engine running.
Shifting into 4
nwill turn Traction Control
and StabiliTrak/Electronic Stability Control
(ESC) off. See Traction Control/Electronic
Stability Control 0242.
Automatic Transfer Case
Two-Speed Transfer Case

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
240 Driving and Operating
The actual 4x4 shift request is only made
after the button is released. The 4x4 graphic
will remain flashing until the shift request
has completed.
A DIC message displays. Once the 4x4 shift
has completed, the DIC message disappears,
the 4x4 graphic stops flashing, and the
current setting is indicated.
Brakes
Electric Brake Boost
Vehicles equipped with electric brake boost
have hydraulic brake circuits that are
electronically controlled when the brake
pedal is applied during normal operation.
The system performs routine tests and turns
off within a few minutes after the vehicle is
turned off. Noise may be heard during this
time. If the brake pedal is pressed during
the tests or when the electric brake boost
system is off, a noticeable change in pedal
force and travel may be felt. This is normal.
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
If there is a problem with ABS, this warning
light stays on. SeeAntilock Brake System
(ABS) Warning Light 0112.
ABS does not change the time needed to
get a foot on the brake pedal and does not
always decrease stopping distance. If you
get too close to the vehicle ahead, there will
not be enough time to apply the brakes if
that vehicle suddenly slows or stops. Always
leave enough room ahead to stop, even
with ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down firmly. Hearing and feeling ABS
operate is normal.
Braking in Emergencies
ABS allows steering and braking at the same
time. In many emergencies, steering can
help even more than braking.
Electric Parking Brake
The Electric Parking Brake (EPB) can always
be applied, even if the vehicle is off. In case
of insufficient electrical power, the EPB
cannot be applied or released. To prevent
draining the battery, avoid unnecessary
repeated cycles of the EPB.
The system has a red parking brake status
light and an amber service parking brake
warning light. See Electric Parking Brake
Light 0112 and
Service Electric Parking Brake Light 0112.
There are also parking brake-related Driver
Information Center (DIC) messages.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
Driving and Operating 293
The ITBC system is integrated with the
vehicle’s brake, anti-lock brake, and
StabiliTrak systems. In trailering conditions
that cause the vehicle’s anti-lock 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, anti-lock brake,
or StabiliTrak systems are not functioning
properly, the ITBC system may not function
fully or at all. Make sure all of these
systems are fully operational to allow the
ITBC system to function properly.
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, including
increased stopping distance or trailer
instability which could result in serious(Continued)
Warning (Continued)
injury, death, or property damage. Only
use the ITBC system with electric or
electric over hydraulic trailer brake
systems.
Trailer Brake Control Panel
1. Manual Trailer Brake Apply Lever
2. Trailer Symbol
3. Trailer Gain Adjustment Buttons
The ITBC control panel is on the instrument
panel to the left of the steering column. The
control panel allows adjustment to the
amount of output, referred to as Trailer
Gain, available to the trailer brakes and allows manual application of the trailer
brakes. Use the ITBC control panel and the
DIC trailer brake display page to adjust and
display power output to the trailer brakes.
Trailer Brake DIC Display Page
The ITBC display page indicates:
.Trailer Gain setting
.Output to the trailer brakes
.Trailer connection
.System operational status.
To display:
.Scroll through the DIC menu pages
.Press a Trailer Gain (+) or (−) button
.Activate the Manual Trailer Brake Apply
Lever
TRAILER GAIN:
Press a Trailer Gain button to recall the
current Trailer Gain setting. Each press and
release of the gain buttons will then change
the Trailer Gain setting. Press the Trailer
Gain (+) or (−) to adjust. Press and hold to
continuously adjust the Trailer Gain. To turn
the output to the trailer off, adjust the
Trailer Gain setting to 0.0. This setting can
be adjusted from 0.0 to 10.0 with a trailer
connected or disconnected.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
Vehicle Care 375
8. Release the parking brake only when youare confident it is secured to tow vehicle
and will not roll.
Before going on to the next step, be
sure to take the mechanical key with
you. It will be needed to re-enter the
vehicle after the power is disconnected.
See “Drive Door Key Lock Cylinder
Access” underDoor Locks 015.
9. Disconnect the negative battery cable at the battery and secure the nut and bolt.
Cover the negative battery post with a
non-conductive material to prevent any
contact with the negative battery
terminal.
Caution
Failure to disconnect the negative battery
cable or to have it contact the terminals
can cause damage to the vehicle.
10. Move the steering wheel to make sure the steering column is unlocked.
Caution
If the steering column is locked, vehicle
damage may occur. 11. Rock the vehicle to make sure the
parking brake is not set and transfer case
is in N (Neutral).
Caution
Towing the vehicle with the parking
brake set can damage it. Always release
the parking brake prior to towing the
vehicle.
Disconnecting the Towed Vehicle
Before disconnecting the towed vehicle: 1. Park on a level surface.
2. Connect the battery.
3. Apply the brake pedal.
{Warning
The vehicle can roll when the brake pedal
is released. Always apply and hold the
brake pedal when setting the parking
brake. Make sure the parking brake is
fully engaged before releasing the brake
pedal.
4. Start the engine and shift the transfer case out of N (Neutral) to 2
m. See “Shifting out of N (Neutral)”
under
Four-Wheel Drive 0236. See your dealer
if the transfer case cannot be shifted out
of N (Neutral).
5. Check that the vehicle is in 2
mby
shifting the transmission to R (Reverse)
and then to D (Drive). There should be
movement of the vehicle while shifting.
6. Shift the transmission to P (Park) and turn off the vehicle.
7. Set the parking brake.
8. Release the parking brake.
9. Disconnect the vehicle from the tow vehicle.
10. Reset any lost presets. The outside temperature display will
default to 0 °C (32 °F) but will reset with
normal usage.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
Vehicle Care 379
blades. Bugs, road grime, sap, and a buildup
of vehicle wash/wax treatments may cause
wiper streaking.
Replace the wiper blades if they are worn or
damaged. Damage can be caused by
extreme dusty conditions, sand, salt, heat,
sun, snow, and ice.
Weatherstrips
Apply weatherstrip lubricant on
weatherstrips to make them last longer, seal
better, and not stick or squeak. Lubricate
weatherstrips at least once a year. Hot, dry
climates may require more frequent
application. Black marks from rubber
material on painted surfaces can be removed
by rubbing with a clean cloth. See
Recommended Fluids and Lubricants0395.
Tires
Use a stiff brush with tire cleaner to clean
the tires.
Caution
Using petroleum-based tire dressing
products on the vehicle may damage the
paint finish and/or tires. When applying a
(Continued)
Caution (Continued)
tire dressing, always wipe off any
overspray from all painted surfaces on
the vehicle.
Wheels and Wheel Trim
Use a soft, clean cloth with mild soap and
water to clean the wheels. After rinsing
thoroughly with clean water, dry with a
soft, clean towel. A wax may then be
applied.
Caution
Chrome wheels and chrome wheel trim
may be damaged if the vehicle is not
washed after driving on roads that have
been sprayed with magnesium chloride or
calcium chloride. These are used on roads
for conditions such as dust and ice.
Always wash the chrome with soap and
water after exposure.
Caution
To avoid surface damage on wheels and
wheel trim, do not use strong soaps,
chemicals, abrasive polishes, cleaners,
(Continued)
Caution (Continued)
or brushes. Use only GM approved
cleaners. Do not drive the vehicle through
an automatic car wash that uses silicon
carbide tire/wheel cleaning brushes.
Damage could occur and the repairs
would not be covered by the vehicle
warranty.
Brake System
Visually inspect brake lines and hoses for
proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear
and rotors for surface condition. Inspect
drum brake linings/shoes for wear or cracks.
Inspect all other brake parts.
Steering, Suspension, and Chassis
Components
Visually inspect steering, suspension, and
chassis components for damaged, loose,
or missing parts or signs of wear at least
once a year.
Inspect power steering for proper
attachment, connections, binding, leaks,
cracks, chafing, etc.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
380 Vehicle Care
Visually check constant velocity joint boots
and axle seals for leaks.
At least every other oil change lubricate the
outer tie rod ends.
Control arm ball joints are maintenance-free.
Caution
Lubrication of applicable steering/
suspension points should not be done
unless the temperature is−12 °C (10 °F) or
higher, or damage could result.
Body Component Lubrication
Lubricate all key lock cylinders, hood hinges,
liftgate hinges, steel fuel door hinge and
power assist step hinges, unless the
components are plastic. Applying silicone
grease on weatherstrips with a clean cloth
will make them last longer, seal better, and
not stick or squeak.
Underbody Maintenance
Caution
Avoid pressure washing the vehicle frame.
Use of high-pressure washers can result
in removal of corrosion protection and
possible vehicle damage. At least twice a year, spring and fall, use
plain water to flush any corrosive materials
from the underbody. Take care to
thoroughly clean any areas where mud and
other debris can collect. If equipped with
power assist steps, extend them and then
use a high pressure wash to clean all joints
and gaps.
Do not directly pressure wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or axles and should be replaced.
Sheet Metal Damage
If the vehicle is damaged and requires sheet
metal repair or replacement, make sure the
body repair shop applies anti-corrosion
material to parts repaired or replaced to
restore corrosion protection.
Original manufacturer replacement parts will
provide the corrosion protection while
maintaining the vehicle warranty.
Finish Damage
Quickly repair minor chips and scratches
with touch-up materials available from your
dealer to avoid corrosion. Larger areas of
finish damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and attack
painted vehicle surfaces causing blotchy,
ring-shaped discolorations, and small,
irregular dark spots etched into the paint
surface. See
“Finish Care” previously in this
section.
Interior Care
To prevent dirt particle abrasions, regularly
clean the vehicle's interior. Immediately
remove any soils. Newspapers or dark
garments can transfer color to the vehicle’s
interior.
Use a soft bristle brush to remove dust from
knobs and crevices on the instrument
cluster. Using a mild soap solution,
immediately remove hand lotions,
sunscreen, and insect repellent from all
interior surfaces or permanent damage may
result.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13690484) - 2021 - crc - 8/17/20
Service and Maintenance 387
Extended Idle Use
When the vehicle is used in a way that
requires extended idle time, one hour of use
shall be deemed the same as 53 km (33 mi).
SeeDriver Information Center (DIC) 0119 for
hourmeter.
Air Conditioning Desiccant (Replace Every
Seven Years)
The air conditioning system requires
maintenance every seven years. This service
requires replacement of the desiccant to
help the longevity and efficient operation of
the air conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required Services
Every 12 000 km/7,500 mi
Rotate the tires, if recommended for the
vehicle, and perform the following services.
See Tire Rotation 0352.
.Check engine oil level and oil
life percentage. If needed, change engine
oil and filter, and reset oil life system.
See Engine Oil 0315 and
Engine Oil Life System 0316.
.Check the air filter life percentage.
If necessary, replace the engine air filter
and reset the engine air filter life system.
See Engine Air Filter Life System 0318.
.Check engine coolant level. See Cooling
System 0319.
.Check windshield washer fluid level. See
Washer Fluid 0324.
.Check tire inflation pressures, including
the spare. See Tire Pressure0346.
.Inspect tire wear. See Tire Inspection
0 351.
.Visually check for fluid leaks.
.Inspect brake system. See Exterior Care
0 376.
.Visually inspect steering, suspension, and
chassis components for damage, including
cracks or tears in the rubber boots, loose
or missing parts, or signs of wear at least
once a year. See Exterior Care0376.
Lubricate the suspension and steering
components at least every other oil
change (if equipped with grease fittings).
.Inspect power steering for proper
attachment, connections, binding, leaks,
cracks, chafing, etc.
.Visually inspect halfshafts and drive
shafts for excessive wear, lubricant leaks,
and/or damage including: tube dents or
cracks, constant velocity joint or universal
joint looseness, cracked or missing boots,
loose or missing boot clamps, center
bearing excessive looseness, loose or
missing fasteners, and axle seal leaks.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13690484) - 2021 - crc - 8/17/20
422 Index
Child Restraints (cont'd)Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . 333
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
Climate Control Systems
Dual Automatic . . . . . . . . . . . . . . . . . . . . . . . . 204
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Cluster, Instrument . . . . . . . . . . . . . . . . . . . . . . 102
Collision Damage Repair . . . . . . . . . . . . . . . . . 407
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Connected Services Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Connections Connected Services . . . . . . . . . . . . . . . . . . . . 418
Control Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Traction and Electronic Stability . . . . . . . 242
Control Light Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Control of a Vehicle . . . . . . . . . . . . . . . . . . . . . .214 Controls
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . 144
Convenience Net . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Coolant Engine Temperature Gauge . . . . . . . . . . . . 107
Engine Temperature Warning Light . . . . . 115
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204, 207
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Courtesy Transportation Program . . . . . . . . 406
Coverage Explanations . . . . . . . . . . . . . . . . . . . 176
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Cruise Control, Adaptive . . . . . . . . . . . . . . . . . 253
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Customer Assistance . . . . . . . . . . . . . . . . . . . . . 403 Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Text Telephone (TTY) Users . . . . . . . . . . . . 403
Customer Information Publications Ordering Information . . . . . 408
Customer Satisfaction Procedure . . . . . . . . . 401
Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
D
Damage Repair, Collision . . . . . . . . . . . . . . . . . 407
Danger, Warning, and Caution . . . . . . . . . . . . . .2
Data Collection
Infotainment System . . . . . . . . . . . . . . . . . . . 411 Data Collection (cont'd)
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Data Recorders, Event . . . . . . . . . . . . . . . . . . . . 411
Database Coverage Explanations . . . . . . . . . 176
Daytime Running Lamps (DRL) . . . . . . . . . . . . 135
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . . . .214
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Diagnostics Connected Services . . . . . . . . . . . . . . . . . . . . 419
Distracted Driving . . . . . . . . . . . . . . . . . . . . . . . . . 213
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . 17
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Drive Belt Routing, Engine . . . . . . . . . . . . . . .400
Driver Teen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Driver Assistance Systems . . . . . . . . . . . . . . . 260
Driver Information Center (DIC) . . . . . . . . . . . 119
Driver Mode Control . . . . . . . . . . . . . . . . . . . . . 245
Driver Mode Control Light . . . . . . . . . . . . . . . . 115
Driving Assistance Systems . . . . . . . . . . . . . . . . . . . . 267
Better Fuel Economy . . . . . . . . . . . . . . . . . . . 213
Characteristics and Towing Tips . . . . . . . . 280