1998 GMC SIERRA tires

Loading Your Vehicle
~EE ~NER'S MANUAL FOR ADDITIONAL INFORMATION. TI
The CertificatiodTire label is found on the rear edge of
the driver's door or in the Incomplete Vehicle Document
in the cab.
The label shows the size of your original tires and the
inflation pressures needed to obtain the gross weight
capacity
of your vehicle. This is called the Gross Vehicle
Weight Rating (GVWR). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The CertificatiodTire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR).
To find out the actual loads on
your front and rear axles, you need to
go to a weigh
station and weigh your vehicle. Your dealer can help
you with this. Be sure to spread out your load equally on
both sides
of the centerline.
Never exceed the GVWR
for your vehicle, or the
GAWR for either the front or rear axle.
And,
if you do have a heavy load, you should spread
it out.
A CAUTION:
In the case of a sudden stop or collision, things
carried in the bed of your truck could shift
forward and come into the passenger area,
injuring
you and others. If you put things in the
bed of your truck, you should make sure they are
properly secured.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
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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
the capacity stamped on your step
bumper. You should always use a sway control
if
your trailer will weigh more than the capacity
stamped
on your step bumper. You can ask a hitch
dealer about sway controls.
Don’t tow a trailer at all during the first
500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the first
500 miles (800 km) that you
tow
a trailer, don’t drive over 50 mph (80 kdh) and
don’t make starts at
full throttle. This helps your
engine and other parts
of your vehicle wear in at the
heavier loads.
0 If you have an automatic transmission, you can tow
in OVERDRIVE
(a). 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). If
you have
a manual transmission and you are towing
a trailer, it’s better not to use
FIFTH (5) gear. Just
drive
in FOURTH (4) gear (or, as you need to, a
lower gear).
Three important considerations have
to do with weight:
0 the weight of the trailer,
0 the weight of the trailer tongue
0 and the weight on your vehicle’s tires.
Weigl- - 3e Trailer
How heavy can a trailer safely be?
It depends
on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a
trailer are all important. And,
it can also depend on any
special equipment that you have
on your vehicle.
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A B
If you’re using a weight-carrying hitch, the trailer
tongue (A) should weigh
10 percent of the total loaded
trailer weight
(B j. If you’re using a weight-distributing
hitch, the trailer tongue
(A) should weigh 12 percent of
the total loaded trailer weight (B).
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 inflated to the upper
limit for cold tires.
You’ll find these numbers on the
Certification label at the rear edge
of the driver’s door or
see ”Tire Loading” in the Index. Then be sure you don’t
go over the
GVW limit for your vehicle, including the
weight of the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are a
few reasons
why you’ll need the right hitch. Here are
some rules to follow:
If you use a step-bumper hitch, your bumper could
be damaged
in sharp turns. Make sure you have
ample room when turning to avoid contact between
the trailer and the bumper.
0 If you’ll be pulling a trailer that, when loaded, will
weigh more than
the capacity stamped on your step
bumper, be sure
to use a properly mounted,
weight-distributing hitch and sway control
of the
proper size. This equipment
is very important for
proper vehicle loading and good handling when
you’re driving.
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Safety Chains
You should always attach chains between your vehicle
and your 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 you can turn with your rig.
And, never allow safety chains
to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 Ibs. (450 kg)
loaded, then it needs its own brakes
-- and they must be
adequate. Be sure to read and follow the instructions for
the trailer brakes so you’ll be able to install, adjust and
maintain them properly.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if
0 The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0 The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port
on the master cylinder that sends the fluid to the
rear brakes.
But don’t use copper tubing for this. If you
do,
it will bend and finally 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, 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.
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11. Try to start the vehicle with the dead battery.
If it won’t start after
a few tries, it probably
needs service.
12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
A. Heavy Metal Engine Part
B. Good Battery
C. Dead Battery
Towing Your Vehicle
Try to have your GM dealer or a professional towing
service tow your vehicle. See “Roadside Assistance’’
in
the Index.
If your vehicle has been changed since it was
factory-new, by adding such things
as fog lamps, aero
skirting, or special tires and wheels, these instructions
may not be correct.
Before you do anything, turn on the hazard
warning flashers.
When you call, tell the towing service:
0 That your vehicle has rear-wheel-drive, or that it has
the four-wheel-drive option.
0 The make, model and year of your vehicle.
Whether you can move the shift lever for the
0 If there was an accident, what was damaged.
When
the towing service arrives, let the tow operator
know that this manual contains detailed towing
instructions and illustrations. The operator may want to
see
them.
transmission and transfer case, if you have one.
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Engine Fan Noise If a Tire Goes Flat
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine.
In most everyday driving
conditions, the fan is spinning slower and the clutch
is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading. trailer
towing and/or high outside temperatures, the fan speed
increases as the clutch more
fully engages. So you may
hear an increase
in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts.
It is merely the cooling system functioning
properly. The fan
will slow down when additional
cooling
is not required and the clutch disengages.
You may
also hear this fan noise when you start
the engine.
It will go away as the fan clutch
partially disengages. It‘s
unusual for
a tire to “blow out’’ 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 hils, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
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 goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
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J
E
I
F
C
Chassis Cab Models
A. Nut
B. Retainer
C. Jack Handle Extension
D. Jack Handle Extension
E. Wheel Wrench
E Jack and Tool
Storage Box
G. Ratchet
H. Jack Handle
I. Tool Retainer
J. Jack
If You’re Stuck: In Sand, Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help
you get out when you’re stuck, but
you must use caution.
A CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts
of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
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NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth,
you can destroy your transmission. I
For information about using tire chains on your vehicle,
see “Tire Chains”
in the Index.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If
you have a
four-wheel drive vehicle, shift into
4HI. Then shift back
and forth between
REVERSE (R) and a forward gear
(or with a manual transmission, between FIRST
(1) or
SECOND (2) and REVERSE (R)), spinning the wheels
as little as possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator pedal
when the transmission is
in gear. If that doesn’t get
you out after a few tries, you may need to be towed out.
Or,
you can use your recovery hooks if your vehicle has
them.
If you do need to be towed out, see “Towing
Your Vehicle”
in the Index.
Using the Recovery Hooks
Your vehicle may be equipped with recovery hooks.
The recovery hooks are provided
at the front of your
vehicle.
You may need to use them if you’re stuck
off-road and need to be pulled to some place where
you can continue driving.
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