1994 GMC SIERRA flat tire

find the load on each tire and see the label for the minimum cold inflation
pressures
for that load.
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:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
If your tires have too much air (overinflation), you can get:
Unusual wear
Bad handling
Rough ride
‘Needless damage from road hazards.
When io 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. Simply looking
at the tires
will not tell you the pressure, especially if you have radial tires
- which may look properly inflated even if they’re underinflated.
If your tires have valve caps, be sure to put them back on. They help prevent
leaks by keeping out dirt and moisture.
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Special Tire lnflation
If you have 16 inch tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 km/h) to
75 mph (120
km/h) where legal, inflate tires to 10 psi (70 kPa)
more than the recommended cold inflation pressures.
- You’ll be driving for very long at speeds of 76 mph (120 km/h) to
85 mph (135
km/h) where legal, cold inflation pressures should be
increased by
10 psi (70 kPa) and you must also reduce axle load
capacity by 10%.
Do not drive over 85 mph (135 km/h) even if
it’s legal.
Inflation pressures should never exceed 10 psi (70 kPa) above the
inflation specified for the maximum load of the tire.
If you have 19.5 inch radial tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 km/h) to
70 mph (110 km/h) where legal, inflate tires to 5 psi (35 kPa) more
than the recommended cold inflation pressures, and reduce the
axle load capacity by 4%.
- You’ll be driving for very long at speeds of 7 1 mph (1 15 km/h) to
75 mph (120
km/h) where legal, cold inflation pressures should be
increased by 5 psi (35 kPa) and you must also reduce axle \
load capacity by 12%.
Do not drive over 75 mph (120 km/h) even if
it’s legal.
Inflation pressures should never exceed 20 psi (140 kPa) above the
inflation specified for the maximum load of the tire.
Tire Inspection and Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended in the Maintenance Schedule. See “Scheduled
Maintenance Services” in the Index.
FRT
8
FRT
Use this rotation
pattern.
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If your vehicle has front tires with different load ratings or tread designs
(such
as all season vs. on/off road) than the rear tires, don’t rotate your tires
front
to rear.
After the tires have been rotated, adjust the front and rear inflation pressure
as shown on the CertificatiodTire label. Make certain that all wheel nuts are
properly tightened. See “Wheel
Nut Torque” in the Index.
A CAUTION:
Rust or dirt on a wheel, or on the parts to which it is fastened,
When It’s Time for New Tires
TREAD WEAR
INDICATORS
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
2/32 inch (1.6
mm) or less of tread
remaining.
You need a
new tire if:
0 You can see the indicators at three or more places around the tire.
0 You can see cord or Fabric showing through the tire’s rubber.
0 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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Uniform Tire Quality Grading
The following information relates to the system developed by the Un\
ited
States National Highway Traffic Safety Administration which grade\
s tires
by treadwear, traction and temperature performance. (This applie\
s only to vehicles sold in the United States.)
Treadwear
The treadwear grade is a comparative rating based on the wear rate of the
tire when tested under controlled conditions on a specified gov\
ernment test
course. For example, a tire graded
150 would wear one and a half (1 1/2)
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 charac\
teristics and
climate.
Traction -A, B, C
The traction grades, from highest to lowest are: A, B, and C. They 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 braking
(straight-ahead) traction tests and does not include cornering \
(turning)
traction.
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 laborat\
ory 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 ad not overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination, can cause heat
buildup and possible tire failure.
These grades are molded on the sidewalls
of passenger car tires.
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A Word About Maintenance
We at General Motors want to help you keep your vehicle in good working
condition. But we don’t know exactly how you’ll drive it.
You may drive
very short distances
only a few times a week. Or you may drive long
distances all the time
in very hot, dusty weather. You may use your vehicle
in making deliveries. Or
you may drive it to work, to do errands, or in many
other ways.
Because of
all the different ways people use their GM vehicles, maintenance
needs vary.
You may even need more frequent checks and replacements than
you will find
in the schedules in this section. So please read this section and
note how you drive. If you have any questions on how
to keep your vehicle
in good condition? see your GM dealer, the place many GM owners choose
to have their maintenance work done. Your dealer can be relied upon to use
the proper parts and practices.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps keep your vehicle in good
working condition? but also helps the environment. All recommended
maintenance procedures are important. Improper vehicle maintenance or the
removal
of important components can significantly affect the quality of the
air we breathe. Improper fluid levels or even the wrong tire inflation can
increase the level of emissions from your vehicle. To help protect our
environment, and to help keep your vehicle
in good condition, please
maintain your vehicle properly.
Recording Maintenance Services
The Maintenance Record near the end of this section provides a place for
you to record the maintenance performed on your vehicle. Whenever any
maintenance
is performed, be sure to write it down in the Maintenance
Record. This will help you determine when your next maintenance should
be done.
In addition, it is a good idea to keep your maintenance receipts.
They may be needed to qualify your vehicle warranty repairs.
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Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability
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 this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certification/Tire
label. See “Loading Your Vehicle” or “Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See
the “Recommended Fluid and Lubricants” chart in this section.
Transmission neutral or clutch start switch operation -
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake”
in the Index. Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only
in “P’ (Park) or “N” (Neutral).
On manual transmission vehicles, put the shift lever
in “N” (Neutral), push
the clutch down halfway, and try to start the engine. The starter should work
only when the clutch
is pushed down all the way to the floor.
Steering column lock operation - While parked, try to turn the key to
LOCK in each gear shift position.
With an automatic transmission, the key should
turn to LOCK only when
the gear shift
is in “P” (Park).
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C
Camper Wiring Harness ........................................... 2-83
Capacities/Specification Charts ..................................... 6-91
CarbonMonoxide
............................................... 2-33
CargoLamp
.................................................... 2-52
Cassette Tape Player (see “Audio Systems”
)
Catalyticconverter .............................................. 6-64
Certificationire Label
........................................... 6-65
Changing a Flat Tire
......................................... 5-26, 5-32
Chemical Paint Spotting
........................................... 6-87
Child Restraints (See “Safety Belts”)
CHMSLFeedWire
.............................................. 2-82
Cigarette LightedAshtrays
..... ................................... 2-52
Circuit Breakers (See “Fuses”)
Cleaning
Finishcare
.................................................. 6-85
Glass
....................................................... 6-84
Insideofvehicle
.............................................. 6-81
Instrumentpanel. Top
.......................................... 6-83
Outsideofvehicle
............................................. 6-84
Special Problems
.............................................. 6-82
VinylorLeather
.............................................. 6-83
Wheels and Tires
.............................................. 6-86
Windshield
.................................................. 6-84
Clock
......................................................... 3-18
AM-FM Stereo Audio System with Cassette Deck
................... 3-11
AM-FM Stereo Audio System with Cassette Deck and Equalizer
... 3-14. 3-18
Conversion to Chassis Cab
........................................ 6-70
Coolant (See “Engine”)
Cooling System Capacity
.......................................... 5-17
Crankcase Capacity
.............................................. 6-93
Increasespeed
............................................... 2-46
CruiseControl
.................................................. 2-44
EraseSpeedMemory .......................................... 2-48
OnHills
..................................................... 2-48
Passing
..................................................... 247
Reducespeed
................................................ 2-47
Resume
..................................................... 2-46
Set
......................................................... 2-45
ToGetOutOf
................................................ 2-48
Customer Assistance for the Hearing or Speech Impaired
................. 8-3
Customer Satisfaction Procedure
..................................... 8-2
Daytime Running Lights (Canada Only)
......................... 2.50, 2.75
Indicator Light
.......................................... 2.50. 2.75
Diesel Fuel (See “Fuel”)
DomeLights
.................................................... 2-51
Doors
.......................................................... 2-7
Locks ........................................................ 2-5
Driving Across an Incline
............................................. 4-21
After Off-Road Driving
........................................ 4-22
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Gages (continued) Tachometer
.................................................. 2-69
Voltmeter
.................................................... 2-82
Trip Odometer
................................................ 2-68
HalogenBulbs .................................................. 6-54
Hazard Warning Flashers
........................................... 5-2
Head Restraints
.................................................. 1-5
Headlights
........................................... 2-49,6-53, 6-62
Composite
................................................... 6-54
Halogen
..................................................... 6-54
High Beam Indicator Light
...................................... 2-76
SealedBeam
................................................. 6-53
Heating System (with
A/C) ......................................... 3-6
Rear Window Defogger
......................................... 3-8
Heating System (without A/C)
....................................... 3-5
FanKnob ..................................................... 3-5
FunctionLever
................................................ 3-5
Rear Window Defogger
......................................... 3-8
Hi~h-LowBeam
.............................................. 241
System Controls ............................................... 3-6
Temperature Lever
............................................. 3-5
Highway Hypnosis ............................................... 4-30
Hitches ........................................................ 4-40
Hood
CheclungUnder
.............................................. 6-15
LatchesandHinge ............................................ 6-51
Horn
.......................................................... 2-39
Hydraulicclutch
................................................ 6-34
Grease Fitting
................................................ 6-35
Hydroplaning
................................................... 4-27
I
If You’re Stuck in Sand. Mud. Ice. or Snow ........................... 5-40
Ignitionswitch .................................................. 2-11
Inflation-Tire Pressure ............................................ 6-71
Instrument Panel ................................................ 2-67
Cluster
...................................................... 2-67
Tachometer Cluster
............................................ 2-67
J
Jack Storage ............................................... 5.29, 5.39
Jumpstarting
.................................................... 5-3
K
Key ReleaseLever ............................................... 2-12
Keys
........................................................... 2-3
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