2012 CHEVROLET SUBURBAN cooling

Black plate (21,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-21
.Idles for long periods in traffic.
.Tows a trailer. SeeTrailer
Towing on page 9‑70.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral) while stopped.
If it is safe to do so, pull off
the road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the temperature overheat gauge
is no longer in the overheat zone
or an overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally. If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle
the engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see
“Overheated
Engine Protection Operating Mode”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message is displayed,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended distances and/or towing a trailer
in the overheat protection mode
should be avoided.
Notice:
After driving in the
overheated engine protection
operating mode, to avoid engine
damage, allow the engine to cool
before attempting any repair.
The engine oil will be severely
degraded. Repair the cause of
coolant loss, change the oil and
reset the oil life system. See
Engine Oil on page 10‑7.
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.

Black plate (22,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
10-22 Vehicle Care
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
fans, 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 fannoise 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.
Power Steering Fluid
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
See
Engine Compartment Overview
on page 10‑6 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.
How to Check Power Steering
Fluid
Notice:
Extremely small amounts
of contamination can cause
steering system damage and
cause it to not work properly. Do
not allow contaminants to contact
the fluid side of the reservoir
cap/dipstick or from entering the
reservoir.
To check the power steering fluid:
1. Turn the key off and let the engine compartment cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the fluid level on the dipstick.

Black plate (40,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
10-40 Vehicle Care
FusesUsage
33 Daytime Running
Lamps 2 (If Equipped)
34 Sunroof
35 Key Ignition System,
Theft Deterrent
System
36 Windshield Wiper
37 SEO B2 Upfitter
Usage (Battery)
38 Electric Adjustable
Pedals
39 Climate Controls
(Battery)
40 Airbag System
(Ignition)
41 Amplifier
42 Audio System
43 Miscellaneous
(Ignition), Cruise
Control Fuses
Usage
44 Liftgate Release
45 Airbag System
(Battery)
46 Instrument Panel
Cluster
47 Not Used
48 Auxiliary Climate
Control (Ignition)
49 Center High-Mounted
Stoplamp (CHMSL)
50 Rear Defogger
51 Heated Mirrors
52 SEO B1 Upfitter
Usage (Battery)
53 Accessory Power
Outlet
54 Automatic Level
Control Compressor
Relay Fuses
Usage
55 Climate Controls
(Ignition)
56 Engine Control
Module, Secondary
Fuel Pump (Ignition)
J-Case Fuses Usage
57 Cooling Fan 1
58 Automatic Level
Control Compressor
59 Heavy Duty Antilock
Braking System
60 Cooling Fan 2
61 Antilock Brake
System 1
62 Starter
63 Stud 2 (Trailer
Brakes)
64 Left Bussed Electrical
Center 1

Black plate (41,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-41
J-CaseFuses Usage
65 Electric Running
Boards
66 Not Used
67 Transfer Case
68 Stud 1 (Trailer
Connector Battery
Power)
69 Mid-Bussed Electrical
Center 1
70 Climate Control
Blower
71 Power Liftgate
Module
72 Left Bussed Electrical
Center 2
Relays Usage
FAN HI Cooling Fan High
Speed
FAN LO Cooling Fan Low
Speed Relays Usage
FAN
CNTRL Cooling Fan Control
HDLP
LO/HID Low-Beam Headlamp
FOG
LAMP Front Fog Lamps
A/C
CMPRSR Air Conditioning
Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL
PMP Fuel Pump
PRK
LAMP Parking Lamps
REAR
DEFOG Rear Defogger
RUN/
CRNK Switched PowerInstrument Panel Fuse
Block
The instrument panel fuse block
access door is located on the driver
side edge of the instrument panel.
Pull off the cover to access the fuse
block.

Black plate (63,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-63
to sudden tire failure. The
grade C corresponds to a
level of performance which all
passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B
and A represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law. Warning: The
temperature grade for this tire is
established for a tire that is
properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned
and balanced at the factory to
provide the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancingwill not be necessary on a regular
basis. However, check the
alignment if there is unusual tire
wear or if the vehicle is pulling to
one side or the other. If the vehicle
vibrates when driving on a smooth
road, the tires and wheels might
need to be rebalanced. See your
dealer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts, and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the one it
replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
Notice: The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration,
headlamp aim, bumper height,
vehicle ground clearance, and tire
or tire chain clearance to the
body and chassis.
See If a Tire Goes Flat on
page 10‑65 for more information.

Black plate (6,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
11-6 Service and Maintenance
Footnotes—Maintenance
Schedule Additional Required
Services —Normal
a) Check all fuel and vapor lines
and hoses for proper hook‐up,
routing, and condition. Check that
the purge valve, if the vehicle has
one, works properly. Replace as
needed.
b) Or every four years, whichever
comes first. c)
Do not directly power wash the
transfer case output seals. High
pressure water can overcome the
seals and contaminate the transfer
case fluid. Contaminated fluid will
decrease the life of the transfer
case and should be replaced. d)
Or every five years, whichever
comes first. See Cooling System on
page 10‑15.
e) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.

Black plate (8,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
11-8 Service and Maintenance
Footnotes—Maintenance
Schedule Additional Required
Services —Severe
a) Check all fuel and vapor lines
and hoses for proper hook‐up,
routing, and condition. Check that
the purge valve, if the vehicle has
one, works properly. Replace as
needed.
b) Or every four years, whichever
comes first. c)
Do not directly power wash the
transfer case output seals. High
pressure water can overcome the
seals and contaminate the transfer
case fluid. Contaminated fluid will
decrease the life of the transfer
case and should be replaced.
d) Or every five years, whichever
comes first. See Cooling System on
page 10‑15.
e) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.Special Application
Services
.Severe Commercial Use
Vehicles Only: Lubricate chassis
components every 5 000 km/
3,000 mi.
.Have underbody flushing service
performed once a year.

Black plate (2,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
12-2 Technical Data
Vehicle Data
Capacities and Specifications
If your vehicle is a Hybrid, see the Hybrid manual for more information.
The following approximate capacities are given in metric and English conversions. SeeRecommended Fluids and
Lubricants on page 11‑12 for more information.
Application Capacities
Metric English
Air Conditioning Refrigerant R134a For the air conditioning system refrigerant charge
amount, see the refrigerant label located under the hood. See your dealer for more information.
Cooling System
5.3L V8 17.3 L 18.3 qt
6.0L V8 16.5 L 17.4 qt
Engine Oil with Filter 5.7 L 6.0 qt
Fuel Tank
Regular 98.4 L 26.0 gal
Extended 1500 Series 119.2 L 31.5 gal
Extended 2500 Series 147.6 L 39.0 gal