1994 GMC SIERRA inflation pressure

Checking Things Under the Hood (continued)
Windshield Washer Fluid
................................. 6-45
Brake Master Cylinder
................................... 6-46
Replacing Brake System Parts
................................ 6-49
Other Maintenance Items
.................................... 6-49
Windshield Wiper Blade Inserts
.............................. 6-50
FluidLeakCheck
.......................................... 6-51
Lubrication
............................................... 6-51
Battery .................................................. 6-52
Vehiclestorage
......................................... 6-52
Bulb Replacement
......................................... 6-53
Fuses and Circuit Breakers
.................................. 6-62
Exhaustsystem
........................................... 6-64
Loading Your Vehicle
...................................... 6-64
Tires .................................................... 6-71
Inflation-Tire Pressure
.................................. 6-71
Tire Inspection and Rotation
............................... 6-73
When it’s Time for New Tires
............................. 6-74
Buying New Tires
....................................... 6-76
Uniform Tire Quality Grading
............................. 6-77
Wheel Alignment and Tire Balance
......................... 6-78
Wheel Replacement
..................................... 6-78
Tire Chains
............................................ 6-79
Appearancecare
.......................................... 6-80
Cleaning the Inside of Your Vehicle
......................... 6-81
Cleaning the Outside
of Your Vehicle ....................... 6-84
Appearance Care Materials
.................................. 6-87
Vehicle Identification Number
................................ 6-88
Service Parts Identification
Label ............................. 6-90
Specifications Charts
..................................... 6-91
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Malfunction Indicator
(SERVICE ENGINE SOON) Lamp
The Malfunction Indicator (SERVICE ENGINE SOON) Lamp on your
instrument panel lets you know when
your emission system needs service.
The light
will come on briefly when you start your engine to let you know
that the system is working. If
it does not come on when you start your
engine,
or if it comes on and stays on while you’re driving, your system
may need service. Your vehicle should still be driveable, but
you should
have your system serviced right away.
Secondary Air hjection Reaction (AIR) System
You may have this system. It has a control valve that will direct air to where
it is needed. If the AIR system needs service, your Malfunction Indicator
(SERVICE ENGINE SOON) Lamp on your instrument panel will come on.
Loading Your Vehicle
SEE OWNERS MANUAL FOR ADDITIONAL INFORMATION
BlKG
The Certification/Tire
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
GVWR (Gross Vehicle Weight Rating). The GVWR includes the weight of
the vehicle, all occupants, fuel and cargo.
The Certification/Tire 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.
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Tires
We don’t make tires. Your new vehicle comes with high quality tires made
by a leading tire manufacturer. These tires
are warranted by the tire
manufacturers and their warranties are delivered with
every new vehicle. If
your spare tire is a different brand than your road tires, you will have a tire
warranty folder from each of these manufacturers.
Inflation - Tire Pressure
The Certificatioflire 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 a mile.
You can operate some vehicles at reduced inflation pressures only when
you’ll be carrying reduced loads. On those vehicles, the minimum cold
inflation pressures for a typical reduced load are printed on the “Improved
Ride Tire Pressure’’ label located on the driver’s door. Weigh the vehicle to
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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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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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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
5
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