tire GMC YUKON 2003 Service Manual

If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live
but also where you’ll be driving. A good source for
this information can be state or provincial police.
Consider using a sway control if your trailer will
weigh less than 5,000 lbs. (2 270 kg). You should
always use a sway control if your trailer will
weigh more than 5,000 lbs. (2 270 kg). You can ask
a hitch dealer about sway controls.
Don’t tow a trailer at all during therst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during therst 500 miles (800 km) that you
tow a trailer, don’t drive over 50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions). See“Tow/Haul Mode”later in
this section.Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Tow/Haul Mode
Tow/haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
tow/haul mode is to:
Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
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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
your vehicle. The Gross Vehicle Weight (GVW) includes
the curb weight of the vehicle, any cargo you may carry in
it, and the people who will be riding in the vehicle. And if
you will tow a trailer, you must add the tongue load to the
GVW because your vehicle will be carrying that weight,
too. See Loading Your Vehicle for more information about
your vehicle’s maximum load capacity.If you’re using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
After you’ve loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights
are proper. If they aren’t, you may be able to get them
right simply by moving some items around in the
trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper limit
for cold tires. You’llnd these numbers on the
Certication label at the rear edge of the driver’s door or
see Tire Loading for more information. Then be sure
you don’t go over the GVW limit for your vehicle,
including the weight of the trailer tongue. If you use a
weight distributing hitch, make sure you don’tgo
over the rear axle limit before you apply the weight
distribution spring bars.
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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 the trailer hitch and platform
(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.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good deal
longer, you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
If your vehicle is equipped with four-wheel steering and
if you use it while backing your trailer the same rules
apply. However, with four-wheel steering your rig
will respond more quickly and it may take additional
practice to get used to backing up with four-wheel
steering.
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Windshield Wiper Blade Replacement..............5-59
Tires..............................................................5-60
Inflation -- Tire Pressure................................5-61
Tire Inspection and Rotation...........................5-61
When It Is Time for New Tires.......................5-63
Buying New Tires.........................................5-64
Uniform Tire Quality Grading..........................5-65
Wheel Alignment and Tire Balance..................5-66
Wheel Replacement......................................5-66
Tire Chains..................................................5-68
If a Tire Goes Flat........................................5-69
Changing a Flat Tire.....................................5-69
Spare Tire...................................................5-88
Appearance Care............................................5-88
Cleaning the Inside of Your Vehicle.................5-89
Care of Safety Belts......................................5-91
Weatherstrips...............................................5-91
Cleaning the Outside of Your Vehicle..............5-92Sheet Metal Damage.....................................5-94
Finish Damage.............................................5-94
Underbody Maintenance................................5-94
Chemical Paint Spotting.................................5-94
GM Vehicle Care/Appearance Materials...........5-95
Vehicle Identification......................................5-96
Vehicle Identification Number (VIN).................5-96
Service Parts Identification Label.....................5-97
Electrical System............................................5-97
Add-On Electrical Equipment..........................5-97
Windshield Wiper Fuses................................5-97
Power Windows and Other Power Options.......5-97
Fuses and Circuit Breakers............................5-98
Capacities and Specifications
........................5-106
Capacities and Specifications
........................5-106
Normal Maintenance Replacement Parts
.........5-109
Normal Maintenance Replacement Parts
.........5-109
Section 5 Service and Appearance Care
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Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
SeeBrake System Inspection on page 6-16.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your brakingsystem–for example, when your brake linings wear
down and you need new ones put in–be sure you get
new approved GM replacement parts. If you don’t,
your brakes may no longer work properly. For example,
if someone puts in brake linings that are wrong for
your vehicle, the balance between your front and rear
brakes can change—for the worse. The braking
performance you’ve come to expect can change in many
other ways if someone puts in the wrong replacement
brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-12for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GMC Warranty booklet for details.{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See“Loading Your
Vehicle”in the Index.
Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinated tires are more likely to be
cut, punctured or broken by a sudden
impact—such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If
your tread is badly worn, or if your tires
have been damaged, replace them.
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Ination -- Tire Pressure
The Certification/Tire label, which is on the rear edge of
the driver’s door, shows the correct inflation pressures
for your tires when they’re cold.“Cold”means your
vehicle has been sitting for at least three hours or driven
no more than 1 mile (1.6 km).
Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too muchexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overination), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-63andWheel Replacement
on page 5-66for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-69.
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The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. Thefirst rotation
is the most important. See“Part A: Scheduled
Maintenance Services,”in Section 6, for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certification/Tire label. Make certain that all wheel nuts
are properly tightened. See“Wheel Nut Torque”
underCapacities and Specifications on page 5-106.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See“Changing a Flat
Tire”in the Index.
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When It Is Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining. Some
commercial truck tires may
not have treadwear
indicators.You need a new tire if any of the following statements
are true:•You can see the indicators at three or more places
around the tire.
•You can see cord or fabric showing through the
tire’s rubber.
•The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
•The tire has a bump, bulge or split.
•The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or
location of the damage.
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Buying New Tires
Tofind out what kind and size of tires you need, look at
the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specifications (TPC
Spec) number on each tire’s sidewall. When you get
new tires, get ones with that same TPC Spec number.
That way your vehicle will continue to have tires
that are designed to give proper endurance, handling,
speed rating, traction, ride and other things during
normal service on your vehicle. If your tires have an
all-season tread design, the TPC number will be
followed by an“MS”(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. If your vehicle has 17 inch road
tires (those originally installed on your vehicle)
it is all right to drive with the 16 inch spare tire
that came with your vehicle. When new, your
vehicle included a spare tire and wheel
assembly with the same overall diameter as
your vehicle’s road tires and wheels. Because
this spare tire was developed for use on your
vehicle, it will not affect vehicle handling or
cause damage to your vehicle.
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