1998 GMC SIERRA Owners Manual

Roof Marker Lamps
1. Remove the screws and lift off the lens.
2. Pull the bulb straight out of the socket.
3. Put a new bulb into the socket and push it in until it
is tight.
4. Replace the lens and tighten the screws.
Pickup Box Identification Lamps
(Dual Rear Wheel Pickup Models)
1. Remove the screws and lamp assembly.
2. Unplug the lamp assembly harness.
3. Use a screwdriver to gently pry the individual lamp
from the lamp housing.
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4. Unplug the lamp at the connector.
5. Plug in a new lamp and snap it into the housing.
6. Reinstall the lamp housing.
Taillamps (Pickup Models)
1. Open the tailgate.
2. Remove the two
rear lamp assembly
screws near
the tailgate
latch
and pull out the
lamp assembly.
3. Remove the screws
from the bulb retainer
and take
it off the
lamp assembly.
c
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4. Pull the old bulb straight
out
of the socket.
5. Put in a new bulb and push it straight in until it
is tight.
6. Replace the bulb retainer.
7. Replace the rear lamp assembly and tighten
the screws.
8. Close the tailgate.
Taillamps (Chassis Cab Models)
1. Using your hands, peel the rubber seal away from
the lens.
2. Lift the lens off the
lamp assembly.
3. Slide the socket out of the lamp assembly.
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4. Push in gently on the
bulb, turn it to the
left and remove it from
the socket. Windshield Wiper Blade Replacement
For proper type and length, see “‘Normal Maintenance 1 I
Replacement Parts” in the Index. I i
i
5. Put in a new bulb and, pushing in gently, turn it to
the right until it is tight.
6. Put the socket back in the lamp assembly and replace
the lens and lens seal.
To replace the windshield wiper blade assembly:
1. Lift the wiper arm and rotate the blade until it is
2. Push the release lever and slide the wiper assembly
3. Install a new blade by reversing Steps 1 and 2.
facing away from the windshield.
toward the driver’s side
of the vehicle.
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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
GM Warranty booklet for details.
A CAUTION:
Poorly maintained and improperly used tires
are dangerous.
0
0
0
0
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. Underinflated 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.
Overinflated 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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Inflation -- Tire Pressure
The CertificationlTire label, which is on the rear edge of
the driver’s door, or on the incomplete vehicle document
in the cab, 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 krn).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right.
It’s not. If your tires
don’t have enough
air (underinflation), you can
get the following:
0 Too much flexing
Too much heat
0 Tire overloading
0 Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
0 Bad handling
0 Rough ride
0 Needless damage from road hazards.
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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 6,000 to 8,000 miles
(10 000 to 13 000 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.
See “When It‘s Time for New Tires” and
“Wheel Replacement” later in this section for more
information. If your vehicle has dual rear wheels, also
see “Dual Tire Operation” later
in this section. The purpose
of regular rotation
is to achieve more
uniform wear
for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
1
FRT FRT
[x[
If your vehicle has single rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
If your vehicle has front tires with different load ranges
or tread designs (such as all season vs. on/off road) than
the rear tires, don’t rotate your tires front
to rear.
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~ 11 your
vehicle has dual rear wheels and the load range
’ and tread design for your front tires is the same as your
rear tires, always use one of the correct rotation patterns
shown here when rotating your tires.
r.
If your vehicle has dual rear wheels and the load range
or tread design for your front tires is different from your
rear tires, always use the correct rotation pattern shown
here when rotating your tires. The dual tires are rotated
as a pair, and the inside rear tires become the outside
rear tires.
When you install dual wheels, be sure the vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown
on the
Certificatioflire label. Make certain that all wheel nuts
are properly tightened. See “Wheel Nut Torque’’ in
the Index.
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