2007 BUICK LACROSSE weight

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important
weight to measure because it affects the total
or gross weight of the vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of the
vehicle, any cargo 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. And if you tow a trailer,
you must add the tongue load to the GVW
because the vehicle will be carrying that weight,
too. SeeLoading Your Vehicle on page 319
for more information about the vehicle’s maximum
load capacity.When using a weight-carrying hitch, the trailer
tongue (A) should weigh 10 percent to 15 percent
of the total loaded trailer weight (B).
After the trailer is loaded, weigh the trailer and the
tongue, separately, to see if the weights are
proper. The correct weight could be achieved
simply by moving some items around in the trailer.
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Total Weight on Your 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 Tire-Loading Information label. SeeLoading
Your Vehicle on page 319. Be sure not to go
over the GVW limit for the vehicle, or the GAWR,
including the weight of the trailer tongue. If a
weight distribution hitch is used, 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. 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.
If holes need to be made in the body of the
vehicle to install a trailer hitch, then be sure
to seal the holes later when the hitch is
removed. If the holes are not sealed, deadly
carbon monoxide (CO) from the exhaust
can get into the vehicle. SeeEngine Exhaust
on page 122. Dirt and water can, too.
Safety Chains
Chains should always be attached between the
vehicle and the trailer. Cross the safety chains
under the tongue of the trailer so that the tongue
will not drop to 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 be turned.
And, never allow safety chains to drag on the
ground.
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Trailer Brakes
Does your trailer have its own brakes? Be sure to
read and follow the instructions for the trailer
brakes so you’ll be able to install, adjust
and maintain them properly.
If your vehicle has anti-lock brakes, do not try
to tap into your vehicle’s brake system. If you
do, both brake systems won’t work well, or
at all.
Even if your vehicle doesn’t have anti-lock
brakes, don’t tap into your vehicle’s brake
system if the trailer’s brake system will
use more than 0.02 cubic inch (0.3 cc) of uid
from your vehicle’s master cylinder. If it
does, both braking systems won’t work well.
You could even lose your brakes.
Will the trailer brake parts take 3,000 psi
(20 650 kPa) of pressure? If not, the
trailer brake system must not be used with
your vehicle.
If everything checks out this far, then make
the brake uid tap at the upper rear master
cylinder port. But don’t use copper tubing
for this. If you do, it will bend and break off.
Use steel brake tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
get to know the 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 is now a good deal longer and not nearly
as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connector,
lamps, tires, and mirror adjustment. 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 lets you check the 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.
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(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 range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.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/
transaxle, 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.
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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. SeeInation - Tire Pressure
on page 409.
Curb Weight:This means 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 319.
GAWR FRT:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 319.
GAWR RR:Gross Axle Weight Rating for the
rear axle. SeeLoading Your Vehicle on page 319.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 may 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.
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Normal Occupant Weight:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). SeeLoading Your Vehicle
on page 319.
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
Ination - Tire Pressure on page 409andLoading
Your Vehicle on page 319.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 1/16 inch (1.6 mm) of tread remains.
SeeWhen It Is Time for New Tires on page 417.
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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 421.
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 319.
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 319.Ination - Tire Pressure
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 hazards
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A Tire and Loading Information label is attached
to the vehicle’s center pillar (B-pillar). 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,
seeLoading Your Vehicle on page 319. 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, it should be
at 60 psi (420 kPa). For additional information
regarding the compact spare tire, seeCompact
Spare Tire on page 437.
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
are under-inated. 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
ination 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.
Re-check 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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