2008 GMC YUKON XL weight

The effect of tongue weight is about 1.5 times the actual
weight. Dividing the 900 lbs (408 kg) by 1.5 leaves you
with being able to handle only 600 lbs (272 kg) of tongue
weight. Since tongue weight is usually at least 10 percent
of total loaded trailer weight, you can expect that the
largest trailer your vehicle can properly handle is
6,000 lbs (2 721 kg).
It is important that you make sure your vehicle does not
exceed any of its ratings — GCWR, GVWR, RGAWR,
Maximum Trailer Rating or Tongue Weight. The
only way to be sure you are not exceeding any of these
ratings is to weigh your vehicle and trailer.Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper limit
for cold tires. You’ll nd these numbers on the
Certication label at the rear edge of the driver’s door or
seeLoading Your Vehicle on page 4-35for more
information. Then be sure you don’t go over the GVW
limit for your vehicle, or the GAWR, including the weight
of the trailer tongue. If you use a weight distributing
hitch, make sure you don’t go over the rear axle
limit before you apply the weight distribution spring bars.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you will need the right hitch.
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Weight-Distributing Hitches and Weight
Carrying Hitches
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 you use a step-bumper hitch, 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 you will be pulling a trailer that, when loaded, 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. You can ask a
hitch dealer/retailer about sway controls.
Safety Chains
You should always attach safety chains between your
vehicle and your 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.
Attach the safety chains to the attaching point on the
hitch platform. If you are towing with an aftermarket
hitch, following the trailer or hitch manufacturer’s
recommendation for attaching safety chains. Always
leave just enough slack so you can turn with your rig.
Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 2,000 lbs (900 kg)
loaded, then it needs its own brakes – and they must be
adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install,
adjust and maintain them properly. (A) Body to Ground Distance (B) Front of Vehicle
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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You cannot see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-47. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. SeeClimate Control System
on page 3-23.Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
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*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/retailer 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.
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/retailer 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 4-49.
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Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire has built up
heat from driving. SeeInflation - Tire Pressure
on page 5-72.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading Your Vehicle on page 4-35.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on
page 4-35.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. SeeLoading Your Vehicle on page 4-35.
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Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT-Metric) Tire
:A tire used on
light duty trucks and some multipurpose passenger
vehicles.
Load Index
:An assigned number ranging from
1 to 279 that corresponds to the load carrying
capacity of a tire.
Maximum Ination Pressure
:The maximum air
pressure to which a cold tire can be inated.
The maximum air pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible ination pressure
for that tire.
Maximum Loaded Vehicle Weight
:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight
:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). SeeLoading Your Vehicle
on page 4-35.Occupant Distribution
:Designated seating
positions.
Outward Facing Sidewall
:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle.
The side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher
or deeper than the same moldings on the other
sidewall of the tire.
Passenger (P-Metric) Tire
:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Ination Pressure
:Vehicle
manufacturer’s recommended tire ination
pressure as shown on the tire placard. See
Inflation - Tire Pressure on page 5-72andLoading
Your Vehicle on page 4-35.
Radial Ply Tire
:A pneumatic tire in which the
ply cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim
:A metal support for a tire and upon which
the tire beads are seated.
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Sidewall:The portion of a tire between the tread
and the bead.
Speed Rating
:An alphanumeric code assigned to
a tire indicating the maximum speed at which a
tire can operate.
Traction
:The friction between the tire and the
road surface. The amount of grip provided.
Tread
:The portion of a tire that comes into
contact with the road.
Treadwear Indicators
:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. SeeWhen It Is Time for New Tires on
page 5-80.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-83.Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
Your Vehicle on page 4-35.
Vehicle Maximum Load on the Tire
:Load on an
individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard
:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended ination pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 4-35.
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Ination - Tire Pressure
If your vehicle is a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information.
Tires need the correct amount of air pressure
to operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is
not. If your tires do not have enough air
(under-ination), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazardsA vehicle specic Tire and Loading Information
label is attached to your vehicle. This label shows
your vehicle’s original equipment tires and the
correct ination pressures for your tires when they
are cold. The recommended cold tire ination
pressure, shown on the label, is the minimum
amount of air pressure needed to support
your vehicle’s maximum load carrying capacity.
For additional information regarding how much
weight your vehicle can carry, and an example of
the Tire and Loading Information label, see
Loading Your Vehicle on page 4-35. How you load
your vehicle affects vehicle handling and ride
comfort. Never load your vehicle with more weight
than it was designed to carry.
When to Check
Check your tires once a month or more.
Do not forget to check the pressure of the spare
tire. SeeSpare Tire on page 5-107for additional
information.
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