2003 GMC SIERRA ESP

Driving with a Trailer
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.
While towing a trailer or when exposed to long periods
of sunshine, theoor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
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.
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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Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmissionuid (don’t overll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help yound them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change thefluid andfilter every
100,000 miles (166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littlefluid can damage
your transmission. Too much can mean that some
of thefluid could come out and fall on hot engine
part or exhaust system parts, starting afire.
Too littlefluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionfluid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C).
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3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-15.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.) If
thefluid level is low, add only enough of the properfluid
to bring the level up to the HOT area for a hot check.
It doesn’t take muchfluid, generally less than one
pint (0.5 L).Don’t overfill.
Notice:We recommend you use onlyfluid labeled
DEXRON
®-III, becausefluid with that label is
made especially for your automatic transmission.
Damage caused byfluid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under“How to Check”.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction–AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
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Temperature–A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a specified indoor
laboratory test wheel. Sustained high temperature can
cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a
level of performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.Scheduled wheel alignment and wheel balancing are
not needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
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Tire Chains
{CAUTION:
Don’t use tire chains. There’s not enough
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of your
vehicle and you or others may be injured in a
crash. Use another type of traction device only
if its manufacturer recommends it for use on
your vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels. If you dofind traction devices
that willfit, install them on the rear tires.
If a Tire Goes Flat
It’s unusual for a tire to“blowout”while you’re driving,
especially if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But if you should ever have a“blowout”, here are a few
tips about what to expect and what to do:
If a front tire fails, theflat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheelfirmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop—well off the road if possible.
If a tire goesflat, the next part shows how to use your
jacking equipment to change aflat tire safely.
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Usage Fluid/Lubricant
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Floor Shift
LinkageLubriplate Lubricant Aerosol (GM
Part No. U.S. 12346293, in Canada
992723, or equivalent) or lubricant
meeting requirements of NLGI #2
Category LB or GC-LB.
Chassis
LubricationChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Front AxleSAE 75W-90 Synthetic Axle
Lubricant (GM Part No. U.S.
12378261, in Canada 10953455) or
equivalent meeting GM Specication
9986115.
Rear Axle
(Steerable)Synthetic Axle Lubricant; use only
GM Part No. 12378557 (in Canada
88901362). Do not add friction
modier.
Transfer CaseDEXRON
®-III Automatic
Transmission Fluid.
Rear Driveline
Center SplineChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Usage Fluid/Lubricant
Front Axle
Propshaft
SplineSpline Lubricant, Special Lubricant
(GM Part No. U.S. 12345879, in
Canada 10953511) or lubricant
meeting requirements of GM
9985830.
Hood HingesMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Body Door
Hinge Pins,
Tailgate Hinge
and Linkage,
Folding Seats
and Fuel Door
HingeMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Tailgate Handle
Pivot Points,
Hinges, Latch
Bolt and
LinkageMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474, or equivalent).
Weatherstrip
ConditioningDielectric Silicone Grease (GM Part
No. U.S. 12345579, in Canada
10953014, or equivalent).
Weatherstrip
SqueaksSynthetic Grease with Teon,
Superlube (GM Part No. U.S.
12371287, in Canada 10953437, or
equivalent).
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