2007 CHEVROLET SUBURBAN light

Your vehicle is equipped with a button at the end of
the shift lever which, when pressed, enables
tow/haul. Your vehicle may be equipped with
Autoride
®which further improves your vehicle’s ride
while towing. SeeAutoride®on page 422for more
information. When the button is pressed, a light on
the instrument panel will illuminate to indicate that
Tow/Haul has been selected. Tow/Haul may be
turned off by pressing the button again, at which
time the indicator light on the instrument panel will
turn off. The vehicle will automatically turn off
Tow/Haul every time it is started.
Tow/Haul is designed to be most effective when
the vehicle and trailer combined weight is at
least 75 percent of the vehicle’s Gross Combined
Weight Rating (GCWR). See Weight of the
Trailer later in this section. Tow/Haul is most useful
under the following driving conditions:
When pulling a heavy trailer or a large or
heavy load through rolling terrain.
When pulling a heavy trailer or a large or
heavy load in stop and go traffic.
When pulling a heavy trailer or a large or
heavy load in busy parking lots where
improved low speed control of the vehicle is
desired.Operating the vehicle in tow/haul when lightly
loaded or with no trailer at all will not cause
damage. However, there is no benet to the
selection of Tow/Haul when the vehicle is
unloaded. Such a selection when unloaded may
result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a
heavy trailer or a large or heavy load.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a trailer are all important. It can also depend
on any special equipment that you have on
your vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it has all
the required trailering equipment. The weight
of additional optional equipment, passengers and
cargo in the tow vehicle must be subtracted
from the maximum trailer weight.
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Trailer Wiring Harness
Your vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin
connector, is located at the rear of the vehicle and
is tied to the vehicle’s frame. The harness
connector can be plugged into a seven-pin
universal heavy-duty trailer connector available
through your dealer.The seven-wire harness contains the following
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in
the underhood electrical center, but the wires
are not connected. They should be connected by
your dealer or a qualied service center.
438

Heavy-Duty Trailer Wiring Harness
Package
Your vehicle is equipped with the seven-wire
trailer towing harness. This harness with a
seven-pin universal trailer connector is attached to
a bracket on the hitch platform.The seven-wire harness contains the following
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in
the underhood electrical center, but the wires
are not connected. They should be connected by
your dealer or a qualied service center.
If you are charging a remote (non-vehicle) battery,
press the tow/haul mode button located at the
end of the shift lever. This will boost the vehicle
system voltage and properly charge the battery. If
the trailer is too light for tow/haul mode, you
can turn on the headlamps as a second way to
boost the vehicle system and charge the battery.
439

Electric Brake Control Wiring
Provisions
These wiring provisions are included with your
vehicle as part of the trailer wiring package. These
provisions are for an electric brake controller. The
instrument panel contains blunt cut wires near the
data link connector for the trailer brake controller.
The harness contains the following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer or a qualied
service center.
Power Winches
If you wish to use a power winch on your vehicle,
only use it when your vehicle is stationary or
anchored.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR) for your vehicle. CWR is
the maximum weight of the load your vehicle can
carry. It doesn’t include the weight of the people
inside. But you can gure about 150 lbs. (68 kg) for
each seat. The total cargo load must not be
more than your vehicle’s CWR.
Weigh your vehicle with the trailer attached, so
that you won’t go over the GVWR or GAWR. If you
are using a weight-distributing hitch, weigh the
vehicle without the spring bars in place.
You’ll get the best performance if you spread out
the weight of your load the right way, and if
you choose the correct hitch and trailer brakes.
For more information, seeTowing a Trailer
on page 422.
440

If your vehicle has a Driver Information Center
(DIC), the TIGHTEN GAS CAP message will be
displayed if the fuel cap is not properly installed.
{CAUTION:
If a re starts while you are refueling, do
not remove the nozzle. Shut off the ow of
fuel by shutting off the pump or by
notifying the station attendant. Leave the
area immediately.Notice:If you need a new fuel cap, be sure to
get the right type. Your dealer can get one
for you. If you get the wrong type, it may not
t properly. This may cause your malfunction
indicator lamp to light and may damage
your fuel tank and emissions system. See
Malfunction Indicator Lamp on page 253.
454

How to Inspect the Engine Air
Cleaner/Filter
Vehicles With an Air Filter Restriction
Indicator
Locate the air lter restriction indicator on the
engine air cleaner/lter cover. When the indicator
turns black or is in the red/orange “change” zone,
replace the lter and reset the indicator. See the
steps following to replace the engine air cleaner/
lter and to reset the air lter restriction indicator.
Vehicles Without an Air Filter Restriction
Indicator
To inspect the air cleaner/lter, remove the engine
air cleaner/lter from the vehicle by following
Steps 1 through 6. When you have the engine air
cleaner/lter removed, lightly shake it to release
loose dust and dirt. If the engine air cleaner/lter
remains caked with dirt, a new lter is required.
Replacing the Engine Air Cleaner/Filter
and Resetting the Air Filter Restriction
Indicator
1. Locate the air cleaner/lter assembly. See
Engine Compartment Overview on page 458.
2. Loosen the four screws on the cover of the
housing and lift up the cover.
465

Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 473.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to
−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core, or
radiator corrosion. In addition, the engine
coolant may require changing sooner, at the
rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
470

{CAUTION:
If you have too much brake uid, it can
spill on the engine. The uid will burn if
the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system. See “Checking Brake Fluid” in
this section.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System
Warning Light on page 249.
Refer to the Maintenance Schedule to determine
when to check your brake uid. SeeScheduled
Maintenance on page 579.
Checking Brake Fluid
You can check the brake uid without taking off
the cap.
Look at the brake uid
reservoir. The uid level
should be above
MIN. If it is not, have
your brake system
checked to see if there
is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not
over the MAX mark.
487