2010 GMC TERRAIN weight

8-64 Driving and Operating
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
Vehicle Load Limits on page 8‑22.
If a weight-carrying hitch or a
weight-distributing hitch is being
used, the trailer tongue (A) should
weigh 10 to 15 percent of the total
loaded trailer weight (B).
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.
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.

Driving and Operating 8-65
Total Weight on the
Vehicle's Tires
Inflate the vehicle's tires to the
upper limit for cold tires. These
numbers can be found on the
Certification label or seeVehicle
Load Limits
on page 8‑22for more
information. Do not go over the
GVW limit for the vehicle, or the
GAWR, including the weight of the
trailer tongue. If using a weight
distributing hitch, do not go over the
rear axle limit before applying the
weight distribution spring bars.
Towing Equipment
Hitches
Use the correct hitch equipment.
See your dealer/retailer or a hitch
dealer for assistance.
.The rear bumper on the vehicle
is not intended for hitches. Do
not attach rental hitches or other
bumper-type hitches to it. Use
only a frame-mounted hitch that
does not attach to the bumper.
.Will any holes be made in the
body of the vehicle when the
trailer hitch is installed? If there
are, seal the holes when the
hitch is removed. If the holes are
not sealed, dirt, water, and
deadly carbon monoxide (CO)
from the exhaust can get into the
vehicle. See Engine Exhaust
on
page 8‑34.
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.
Leave enough slack so the rig can
turn. Never allow safety chains to
drag on the ground.
Trailer Brakes
Does the trailer have its own
brakes? Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted and
maintained properly.
Because the vehicle has antilock
brakes, do not tap into the vehicle's
brake system. If this is done, both
brake systems will not work well,
or at all.

Vehicle Care 9-49
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in psi (pounds per
square inch) or kPa (kilopascal).
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 psi (pounds per
square inch) or kPa (kilopascal)
before a tire has built up heat
from driving. See Tire Pressure
on page 9‑52. 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 Identification
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 Vehicle Load Limits
on page 8‑22.

9-50 Vehicle Care
GAWR FRT:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits
on
page 8‑22
.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits
on
page 8‑22
.
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 Inflation Pressure
:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The
load rating for a tire at the
maximum permissible inflation
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
68 kg (150 lbs). See Vehicle
Load Limits
on page 8‑22.
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 Inflation
Pressure
:Vehicle
manufacturer's recommended
tire inflation pressure as shown
on the tire placard. See Tire
Pressure
on page 9‑52and
Vehicle Load Limits
on
page 8‑22
.

Vehicle Care 9-51
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.
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 1.6 mm
(1/16 inch) of tread remains.
See When It Is Time for New
Tires
on page 9‑59.
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. See Uniform
Tire Quality Grading
on
page 9‑62
. Vehicle Capacity Weight
:The
number of designated seating
positions multiplied by 68 kg
(150 lbs) plus the rated cargo
load. See Vehicle Load Limits
on
page 8‑22
.
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 inflation pressure.
See “Tire and Loading
Information Label” underVehicle
Load Limits
on page 8‑22.

9-52 Vehicle Care
Tire Pressure
Tires need the correct amount of
air pressure to operate
effectively.
Notice:Do not let anyone tell
you that under‐inflation or
over‐inflation is all right. It is
not. If your tires do not have
enough air (under‐inflation),
you can get the following:
.Too much flexing
.Too much heat
.Tire overloading
.Premature or
irregular wear
.Poor handling
.Reduced fuel economy If your tires have too much air
(over‐inflation), you can get
the following:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from
road hazards
A vehicle specific Tire and
Loading Information label is
attached to your vehicle. This
label shows your vehicle's
original equipment tires and the
correct inflation pressures for
your tires when they are cold.
The recommended cold tire
inflation 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
Vehicle
Load Limits
on page 8‑22. 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 compact spare
tire, if the vehicle has one.
The compact spare should
be at 60 psi (420 kPa). For
additional information regarding
the compact spare tire, see
Compact Spare Tire
on
page 9‑76
.