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Black plate (28,1)Buick Lucerne Owner Manual - 2011
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. Here are
some rules to follow:
.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, then
be sure to seal the holes later 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. SeeEngine
Exhaust
on page 3‑30in the Index for more
information.
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. Follow the
manufacturer's recommendation for attaching safety
chains and do not attach them to the bumper. Always
leave just enough slack so the rig can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
Because the vehicle has antilock brakes, do not try to
tap into the vehicle's hydraulic brake system. If you do,
both brake systems will not work well, or at all.
Does your trailer have its own brakes? Be sure to read
and follow the instructions for the trailer brakes so you
will be able to install, adjust and maintain them properly.
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Black plate (61,1)Buick Lucerne Owner Manual - 2011
(C) Aspect Ratio:A two‐digit number that
indicates the tire height‐to‐width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire's sidewall is 60 percent as high as it
is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the
letter D means diagonal or bias ply construction;
and the letter B means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:These characters
represent the load index and speed rating of the
tire. The load index represents the load carrying
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
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 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. See Inflation - Tire Pressure
on
page 6‑64
.
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.
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Black plate (62,1)Buick Lucerne Owner Manual - 2011
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
Loading the Vehicle
on page 5‑18.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑18.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑18.
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 150 lbs (68 kg). See Loading the Vehicle
on
page 5‑18
.
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.
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