1998 GMC SIERRA tire pressure

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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You need a new tire if any of the following statements
are true:
0 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.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel
nut is replaced, check the wheel nut
torque after 100, 1,000 and 6’000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see “Wheel
Nut Torque”
in the Index. The outer
tire
on a dual wheel setup generally wears
Faster than the inner tire. Your tires will wear more
evenly and last longer if
you rotate the tires periodically.
If you’re going to be doing a lot
of driving on
high-crown roads,
you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure to return to the recommended pressures when
no
longer driving under those conditions. See “Changing a
Flat Tire’’ in the Index for more information.
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire.
You or
others could be injured. Be sure all tires (including
the spare,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at
the CertificatiodTire label.
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Capacities and Specifications
Please refer to ”Recommended Fluids and Lubricants” in the Index for more information.
Engine
“VORTEC” 4300
“VORTEC” 5000
”VORTEC“ 5700
“VORTEC“ 7400
Wheels and Tires
Model
C 1500
K 1500 and C/K 2500
C/K 2500 (w/C6P)
C/K
3500 (Single Rear Wheels)
C/K 3500 (Dual Rear Wheels)
C 3500 HD Front
C 3500 HD Rear
Tire Pressure
Type
V6
V8
V8
V8
VIN Code
w
M
R
J
Spark Plug Gap
0.060 inches ( 1.52 mm)
0.060 inches
(I .52 mm)
0.060 inches (1.52 mm)
0.060 inches (1 32 mm)
Description Torque
5 bolts (14mm) 140 lb-ft ( 190 Nem)
6 bolts
(14mm) 140 Ib-ft (190 N-m)
8 bolts (14mm) 140 lb-ft ( 190 N-m)
8 bolts
(14mm) 140 lb-ft ( 190 N-m)
8 bolts
(14mm) 140 lb-ft (190 Nsm)
5 bolts (5/8 in.) 175 Ib-ft (240 N-m)
10 bolts (5/8 in.)
175 lb-ft (240 Nem)
See the Certificationflire label on the rear edge of the driver’s door
or the incomplete vehicle document
in the cab.
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Part B: Owner Checks and Services
Listed below are owner checks and services which
should be performed at the intervals specified
to help
ensure
the safety, dependability and emission control
performance
of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever
any fluids or lubricants are added to your
vehicle, make sure they are the proper ones.
as shown in
Part D.
At the First 100, 1,000 and 6,000 Miles
(160,1600 and 10 000 km)
For vehicles with dual wheels, check dual wheel nut
torque. For proper torque, see “Wheel Nut Torque” in
the Index.
At Each Fue-
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See “Engine Oil” in the Index for
further details.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL@
coolant mixture if necessary. See “Engine Coolant” in
the Index for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid
if
necessary. See ”Windshield Washer Fluid” in the Index
for ElIrther details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inflated to the correct pressures.
See “Tires”
in the Index for further details.
Cassette Deck Service
Clean cassette deck. Cleaning should be done every
50 hours of tape play. See “Audio Systems“ in the
Index for further details.
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Pregnancy. Use of Safety Belts .................... 1-22
Problems on the Road ............................ 5- 1
Protecting Exterior Bright Metal Parts ............... 6-67
PTO
......................................... 4-61
Publications. Service and Owner
.............. 8- 1 I . 8- I2
Radiator
..................................... 5-20
Radiator Pressure Cap
........................... 6-32
Radio Reception
................................ 3-23
Radios
........................................ 3-7
Rain. Driving
In ................................ 4-28
Rear
Reading
Lamps
................................ 2-44
Axle
.................................. 6-26.7-47
Outside Seat Position
..................... 1-34. 1-38
Safety Belt Comfort Guides ..................... 1-40
Seat Passengers
.............................. 1-34
Towing
..................................... 5-12
Window Defogger ............................. 3-6
RearSeat
.................................. 1-7.1-8
Rearview Mirror
................................ 2-45
Electrochromic Day/Night
...................... 2-46
Inside Day/Night
............................. 2-45
Reclining Seatbacks
.............................. 1-4
Recommended Fluids and Lubricants
............... 7-46
Recovery
Hooks ................................ 5-37
Recovery Tank, Coolant
.......................... 5- 15
Recreational Vehicle Towin?
...................... 4-4 1
Refrigerants, Air Conditionlng .................... 6-79 Replacement
Bulbs
................................. 6.39. 6.76
Wheel
...................................... 6-59
Parts
....................................... 6-78
Replacing Safety Belts ........................... 1-70
Reporting Safety Defects ......................... 8-10
Restraints Checking
................................... 1-70
Child
....................................... 1-45
Head
........................................ 1-5
Replacing Parts After
a Crash ................... 1-70
System Check ................................ 7-41
Right Front Passenger Position
.................... 1-23
Roadside Assistance .............................. 8-5
Roadside Assistance. Canadian
..................... 8-7
Rocking Your Vehicle ........................... 5-37
Roof Marker Lamp Bulb Replacement
.............. 6-47
Rotation
. Tires ............................ 6-53. 6-54
Safety Bell Extender ............................ 1-70
Safety Belts .................................... 1-9
Adults ...................................... 1-14
Care
....................................... 6-64
Children .................................... 1-42
Driver Position
............................... 1-14
Extender
.................................... 1-70
Incorrect Usage
.................... 1 . 17. 1.68. 1-69
Center
Passenger Position
...................... 1-32
How to Wear Properly ......................... 1-14
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Steering ....................................... 4-8
In Emergencies ............................... 4- 10
Power ....................................... 4-8
Speed Sensitive
............................... 4-9
Tips
......................................... 4-9
Wheel’Tilt
.................................. 2-34
Step-Bumper Pad
............................... 4-63
Storage Areas
.................................. 2-5 1
Storage. Overhead .............................. 2-5 1
Storage. Vehicle ................................ 6-39
Stuck: In Sand. Mud. Ice or Snow
.................. 5-36
Sunvisors
.................................... 2-59
Sunglasses Storage
.............................. 2-53
Symbols. Vehicle
.................................. v
Tachometer .................................. 2-63
Tailgate Removal
................................ 2-3
Taillamp Bulb Replacement
.................. 6-48’6-49
Tape Player Care
............................... 3-25
Temperature Control. Climate Control System
..... 3-2. 3-3
Theft
.......................................... 2-9
Theft-Deterrent Feature .......................... 3-2 1
THEFTLOCK” ................................ 3-21
Thermostat
.................................... 6-32
Third Door
..................................... 2-4
Tilt Steering Wheel
............................. 2-34
Time. Setting the
................................ 3-7
Tire Chains
.................................... 6-60
TireLoading
................................... 4-43 Tires
......................................... 6-51
Alignment and Balance
........................ 6-59
BuyingNew
................................. 6-56
Chains
..................................... 6-60
Changing
a Flat .............................. 5-23
Cleaning
.................................... 6-67
Dual Operation
............................... 6-56
Inflation
.................................... 6-52
Inflation Check
............................... 7-40
Inspection and Rotation
........................ 6-53
Loading
.................................... 4-43
Pressure
.................................... 6-52
Temperature
................................. 6-58
Traction
.................................... 6-58
Treadwear
................................... 6-58
Uniform Quality Grading
....................... 6-57
Wear Indicators
.............................. 6-55
Wheel Replacement
........................... 6-59
When It’s Time for New
....................... 6-55
TopStrap
..................................... 1-50
TorqueLock ................................... 2-28
Torque, Wheel
Nut ......................... 5-32, 6-77
Towing
a Trailer ................................ 4-49
Towing, Recreational Vehicle
..................... 4-41
Towing Your Vehicle
............................. 5-8
Trailer Brakes
..................................... 4-56
Driving on Grades
............................ 4-58
Driving with
................................. 4-56
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