weight GMC ENVOY DENALI 2009 Owner's Manual

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/Tire Label located on the B-pillar below the
door latch or seeLoading the Vehicle on page 4-31
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.
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Weight Distributing Hitches and Weight
Carrying Hitches
When using a weight-distributing hitch, the hitch must be
adjusted so that the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.
If a step-bumper hitch is 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 pulling a trailer that, when loaded, will weigh more than
4,000 lbs (1 814 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. Always leave just
enough slack so the rig can turn. Never allow safety
chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more than 1,500 lbs
(680 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 brake
system. (A) Body to Ground Distance, (B) Front of Vehicle
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Driving with a Trailer
{CAUTION:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
Have the exhaust system inspected for leaks
and make necessary repairs before starting
a trip.
Never drive with the liftgate, trunk/hatch, or
rear-most window open.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-37.Towing a trailer requires a certain amount of experience.
Get to know the rig before setting out for the open road.
Get acquainted 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 longer and not as
responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This checks the electrical connection
at the same time.
During the 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 the vehicle without a trailer.
This can help to avoid situations that require heavy
braking and sudden turns.
Passing
More passing distance is needed when towing a trailer.
Because the rig is longer, it is necessary to go much
farther beyond the passed vehicle before returning to
the lane.
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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 5-60.
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 the Vehicle on page 4-31.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading the Vehicle on page 4-31.
GAWR RR
:Gross Axle Weight Rating for the
rear axle. SeeLoading the Vehicle on page 4-31.
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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 the Vehicle on
page 4-31.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 5-60andLoading
the Vehicle on page 4-31.
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 5-69.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratingsare determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-72.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
the Vehicle on page 4-31.
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 the
Vehicle on page 4-31.
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For additional information regarding how much
weight your vehicle can carry, and an example
of the Tire and Loading Information label,
seeLoading the Vehicle on page 4-31. 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, if the vehicle has one. SeeSpare Tire on
page 5-102for additional information.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly
inated simply by looking at them. Radial tires
may look properly inated even when they areunderinated. Check the tire’s ination pressure
when the tires are cold. Cold means your vehicle
has been sitting for at least three hours or driven
no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out
dirt and moisture.
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