CHEVROLET SUBURBAN 2009 Owners Manual

Vehicle Axle Ratio Maximum Trailer Weight GCWR*
5.3L V8 K5L HD Cooling Pkg 3.42 8,100 lbs (3 674 kg) 14,000 lbs (6 350 kg)
6.0L V8 3.42 8,100 lbs (3 674 kg) 14,000 lbs (6 350 kg)
1500 Series 4WD Short Wheel Base
5.3L V8 3.42 5,700 lbs (2 586 kg) 11,500 lbs (5 216 kg)
5.3L V8 K5L HD Cooling Pkg 3.42 8,200 lbs (3 720 kg) 14,000 lbs (6 350 kg)
6.2L V8 3.42 8,100 lbs (3 674 kg) 14,000 lbs (6 350 kg)
1500 Series 4WD Long Wheel Base
5.3L V8 3.42 5,400 lbs (2 449 kg) 11,500 lbs (5 216 kg)
5.3L V8 K5L HD Cooling Pkg 3.42 7,900 lbs (3 583 kg) 14,000 lbs (6 350 kg)
6.0L V8 3.42 7,900 lbs (3 583 kg) 14,000 lbs (6 350 kg)
2500 Series 2WD Long Wheel Base
6.0L V8 3.73 9,600 lbs (4 355 kg) 16,000 lbs (7 257 kg)
2500 Series 4WD Long Wheel Base
6.0L V8 3.73 9,300 lbs (4 218 kg) 16,000 lbs (7 257 kg)
*The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversions. The GCWR for the vehicle should not be
exceeded.
Ask your dealer/retailer for our trailering information or
advice, or write us at our Customer Assistance Offices.
SeeCustomer Assistance Offices on page 7-6for more
information.
4-53

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total gross weight of the
vehicle. The Gross Vehicle Weight (GVW) includes the
curb weight of the vehicle, any cargo carried in it, and the
people who will be riding in the vehicle. If there are a lot of
options, equipment, passengers or cargo in the vehicle, it
will reduce the tongue weight the vehicle can carry, which
will also reduce the trailer weight the vehicle can tow.
If towing a trailer, the tongue load must be added to the
GVW because the vehicle will be carrying that weight,
too. See for more information about the vehicle’s
maximum load capacity.The trailer tongue weight (A) should be 10 percent to
15 percent of the total loaded trailer weight (B), up to a
maximum of 600 lbs (272 kg) with a weight carrying
hitch or up to a maximum of 1,000 lbs (453 kg) with a
weight distributing hitch. For more information, see
Weight-Distributing Hitches and Weight Carrying
Hitches later in this section.
4-54

Do not exceed the maximum allowable tongue weight
for the vehicle. Choose the shortest hitch extension
that will position the hitch ball closest to the vehicle.
This will help reduce the effect of trailer tongue weight
on the rear axle.
After loading the trailer, weigh the trailer and then the
tongue, separately, to see if the weights are proper.
If they are not, adjustments might be made by moving
some items around in the trailer.
Trailering may be limited by the vehicle’s ability to carry
tongue weight. Tongue weight cannot cause the vehicle
to exceed the GVWR (Gross Vehicle Weight Rating) or
the RGAWR (Rear Gross Axle Weight Rating). The effect
of additional weight may reduce the trailering capacity
more than the total of the additional weight.Consider the following example:
A vehicle model base weight is 5,500 lbs (2 495 kg);
2,800 lbs (1 270 kg) at the front axle and 2,700 lbs
(1 225 kg) at the rear axle. It has a GVWR of 7,200 lbs
(3 266 kg), a RGAWR of 4,000 lbs (1 814 kg) and a
GCWR (Gross Combination Weight Rating) of 14,000 lbs
(6 350 kg). The trailer rating should be:
Expect tongue weight to be at least 10 percent of
trailer weight (850 lbs (386 kg)) and because the weight
is applied well behind the rear axle, the effect on the
rear axle is greater than just the weight itself, as much
as 1.5 times as much. The weight at the rear axle could
be 850 lbs (386 kg) X 1.5 = 1,275 lbs (578 kg). Since the
rear axle already weighs 2,700 lbs (1 225 kg), adding
1,275 lbs (578 kg) brings the total to 3,975 lbs (1 803 kg).
This is very close to, but within the limit for RGAWR
as well. The vehicle is set to trailer up to 8,500 lbs
(3 856 kg).
4-55

If the vehicle has many options and there is a front
seat passenger and two rear seat passengers with some
luggage and gear in the vehicle as well. 300 lbs (136 kg)
could be added to the front axle weight and 400 lbs
(181 kg) to the rear axle weight. The vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
might think 700 additional pounds (318 kg) should be
subtracted from the trailering capacity to stay within
GCWR limits. The maximum trailer would only be
7,800 lbs (3 538 kg). You may go further and think the
tongue weight should be limited to less than 1,000 lbs
(454 kg) to avoid exceeding GVWR. But the effect on the
rear axle must still be considered. Because the rear axle
now weighs 3,100 lbs (1 406 kg), 900 lbs (408 kg) can
be put on the rear axle without exceeding RGAWR.
The effect of tongue weight is about 1.5 times the actual
weight. Dividing the 900 lbs (408 kg) by 1.5 leaves only
600 lbs (272 kg) of tongue weight that can be handled.Since tongue weight is usually at least 10 percent of total
loaded trailer weight, expect that the largest trailer the
vehicle can properly handle is 6,000 lbs (2 721 kg).
It is important that the vehicle does not exceed any of
its ratings — GCWR, GVWR, RGAWR, Maximum Trailer
Rating or Tongue Weight. The only way to be sure it
is not exceeding any of these ratings is to weigh
the vehicle and trailer.
Total Weight on the Vehicle’s Tires
Be sure the vehicle’s tires are inated to the upper
limit for cold tires. These numbers can be found on the
Certication label at the rear edge of the driver’s door or
see Loading Your Vehicle for more information. Make
sure not to go over the GVW limit for the vehicle, or the
GAWR, including the weight of the trailer tongue. If using
a weight distributing hitch, make sure not to go over the
rear axle limit before applying the weight distribution
spring bars.
Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why the right hitch is needed.
4-56

Weight-Distributing Hitches and Weight
Carrying Hitches
A:Body to Ground Distance
B:Front of Vehicle
When using a weight-distributing hitch, the hitch must
be adjusted so the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.If a step-bumper hitch will be used, the bumper could be
damaged in sharp turns. Make sure there is ample room
when turning to avoid contact between the trailer and the
bumper.
If the loaded trailer being pulled will weigh more than
5,000 lbs (2 270 kg), be sure to use a properly mounted
weight-distributing hitch and sway control of the proper
size. This equipment is very important for proper vehicle
loading and good handling when driving. Always use a
sway control if the trailer will weigh more than these
limits. Ask a hitch dealer about sway controls.
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 being towed
weighs up to the vehicle’s trailer rating limit, safety chains
may be attached to the attaching point on the hitch
platform. Always leave just enough slack so the rig can
turn. Never allow safety chains to drag on the ground.
4-57

Tow/Haul Mode
Pressing this button at
the end of the shift lever
turns on and off the
tow/haul mode.
This indicator light on the
instrument panel cluster
comes on when the
tow/haul mode is on.
Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. SeeTow/Haul Mode
on page 2-38for more information.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” earlier in the 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.
4-58

Trailer Brakes
A loaded trailer that weighs more than 2,000 lbs (900 kg)
needs to have its own brake system that is adequate for
the weight of the trailer. Be sure to read and follow the
instructions for the trailer brakes so they are installed,
adjusted and maintained properly.
Since the vehicle is equipped with StabiliTrak
®, the
trailer brakes cannot tap into the vehicle’s hydraulic
system.
Integrated Trailer Brake Control
System
The vehicle may have an
Integrated Trailer Brake
Control (ITBC) system
for electric trailer brakes.This symbol is located on the Trailer Brake Control
Panel on vehicles with an Integrated Trailer Brake Control
System. The power output to the trailer brakes is based
on the amount of brake pressure being applied by the
vehicle’s brake system. 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,
anti-lock brake and StabiliTrak (if equipped) 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 the StabiliTrak system.
If the vehicle’s brake, anti-lock 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.
4-59

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 or in RUN.
The ITBC system can only be used with trailers with
electric brakes.
{CAUTION:
Connecting a trailer that is not compatible with the
ITBC 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. An aftermarket controller
may be available for use with trailers with surge,
air or electric-over-hydraulic trailer brake systems.
To determine the type of brakes on the trailer and
the availability of controllers, check with your trailer
manufacturer or dealer/retailer.When trailering, make sure of the following:
The ITBC system is used only with trailers that are
equipped with electric brakes.
All applicable local and federal laws and regulations
are followed.
All electrical and mechanical connections to the
trailer are made correctly.
The trailer’s brakes are in proper working condition.
The trailer and vehicle are properly loaded for
the towing condition.
The ITBC system is a factory installed item.
Out-of-factory installation of this system should not
be attempted. GM is not responsible for warranty
or performance of the system resulting from
out-of-factory installation.
4-60

Trailer Brake Control Panel
A. Manual Trailer Brake Apply Lever
B. Trailer Gain Adjustment ButtonsThe ITBC system has a control panel located on the
instrument panel to the left of the steering column.
SeeInstrument Panel Overview on page 3-4for more
information on location. The control panel allows
adjustment the amount of output, referred to as trailer
gain, available to the electric trailer brakes and allows
manual application the trailer brakes. The Trailer Brake
Control Panel is used along with the Trailer Brake Display
Page on the DIC to adjust and display power output to the
trailer brakes.
4-61

Trailer Brake DIC Display Page
The ITBC system displays messages into the vehicle’s
Driver Information Center (DIC). SeeDIC Warnings
and Messages on page 3-64for more information.
The display page indicates Trailer Gain setting, power
output to the electric trailer brakes, trailer connection
and system operational status.
A. Trailer Gain Setting
B. Power Output to Trailer Brakes
C. No trailer with electric brakes connected or fault
presentThe Trailer Brake Display Page can be displayed by
performing any of the following actions:Scrolling through the DIC menu pages using the
odometer trip stem or the DIC Vehicle Information
button (if equipped).
Pressing a Trailer Gain button – If the Trailer Brake
Display Page is not currently displayed, pressing a
Trailer Gain button will rst recall the current Trailer
Gain setting. After the Trailer Brake Display Page
is displayed, each press and release of the gain
buttons will then cause the Trailer Gain setting to
change.
Activating the Manual Trailer Brake Apply lever
Connecting a trailer equipped with electric trailer
brakes
All DIC warning and service messages must rst be
acknowledged by the driver by pressing the odometer trip
stem or the DIC Vehicle Information button (if equipped)
before the Trailer Brake Display Page can be displayed
and Trailer Gain can be adjusted.
4-62