1994 GMC SIERRA wheel

Brake Adjustment
Every time you make a brake stop, your disc brakes adjust for wear.
If your brake pedal goes down farther than normal, your rear drum brakes
may need adjustment. Adjust them by backing up and firmly applying
the
brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its many parts have to
be of top quality and work well together if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly.
For example,
if someone puts in brake linings that are wrong for your
vehicle, the balance between your front and rear brakes can change, for
the
worse. The braking performance you’ve come to expect can change in many
other ways if someone puts in the wrong replacement brake parts.
Other Maintenance Hems
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings.
See “Recommended Fluids and Lubricants”
in the Index for the proper
lubricant to use.
Front Wheel Bearings
Your vehicle has front wheel bearings that must be cleaned and repacked.
Your maintenance schedule
will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control
the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be
the same as the original equipment shock absorbers in both
extended length and strength.
NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers
or suspension system
could be damaged.
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Wheel Nut Torque
For vehicle with dual wheels, wnen the vehicle, wheel or Tasteners are new,
have the torque set at
the first 100, 1,000 and 6,000 miles (1 60, 1600 and
9600 km). Use the torque specified
in the appropriate Specification Chart
later
in this section.
Single Belt Accessory Drive
If your new vehicle uses a serpentine belt, it is lighter and more durable than
systems with several belts.
The belt runs over or around the pulleys on the engine.
A tensioner may be
used
to keep the belt tight at all times. The tensioner also makes replacing
the belt easier.
If you need to replace the belt, be sure to get the correct
replacement belt. Your dealership or parts supplier can help you with this.
The Accessory Drive belt Routing label on your vehicle will show
you how
to route
the belt your vehicle uses.
Windshield Wiper Blade Inserts
To replace the
windshield wiper
blade insert, lift the
wiper arm and rotate
the blade until
it is
facing away from the
windshield.
Unlatch
the end of the insert from the holding clips. Remove the insert and
slide a new
one in place. Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditioning
system
to be sure it has not lost any cooling ability. If you think the system
is not working properly, have your dealership check it out as soon as
possible.
The air conditioning
will not work when the temperature is below 40°F
(4°C).
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Fender Marker Lights-
Dual Rear Wheel Pickup Models
1.
2.
3.
Remove the screws and take
the fender marker
assembly out
of
the fender.
Turn the bulb
socket to the left
and remove it
from the lens assembly.
Pull the bulb straight out of the
socket.
4. Put a new bulb into the socket and push it in until it is tight.
5. Put the socket back into the lens assembly and turn it to th\
e right to
tighten it.
6. Replace the lens and tighten the screws.
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After you’ve loaded your vehicle and camper, drive to a weigh station and
weigh
on the front and rear wheels separately. This will tell you the loads on
your axles. The loads
on the front and rear axles shouldn’t be more than
either of the GAWRs. The total
of the axle loads should not be more than
the GVWR.
Open your driver’s door and look at
the CertificatiodTire label to find out
your CWAR and GVWR.
If
you’ve gone over your weight ratings, move or take out some things until
all the weights fall below the ratings. Of course, you should always tie down
any loose items when you load your vehicle or camper.
When you install and load your slide-in camper, check the manufacturer’s
instructions.
If
you want more information on curb weights, cargo weights, cargo weight
rating and the correct center of gravity zone for your vehicle, your dealer
can help
you. Just ask for a copy of “Consumer Information, Truck-Camper
Loading.”
Trailer Recommendations
You must subtract your hitch loads from the CWR for your vehicle. Weigh
your vehicle with
the trailer hitch attached, so that you won’t go over the
GVWR or the GAWR.
You’ll get the best performance if you spread out the weight of your load
the right way, and if‘ you choose the correct hitch and trailer brakes.
For more information, see “Trailer Towing’’
in the Index.
Pickup Conversion To Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and
a commercial or recreational body installed.
Before
you do so, first contact the GM Zone Office for your area for
information on such conversions. (See the “Warranty and Owner
Assistance” booklet for Zone Office.) Owners should be aware that, as
manufactured, there are differences between a chassis cab and a pickup with
the box removed which may affect vehicle safety. The components
necessary to adapt
the pickup to permit its safe use with a specialized body
should be installed by a body builder
in accordance with the information
available from
the Zone Office.
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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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Dual Tire Rotation
n
Use one of these
patterns if you have
the same tire sizes and
load ranges on
the
front and rear.
Use
this pattern if
your front and rear
tires are different sizes
or load ranges. The
dual rear 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 wheels are lined
UP.
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Dual lire Operation
If your vehicle has dual rear wheels, the outer tire will usually wear 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.
Buying New Tires
To find out what kind and size of tires you need, look at the
CertificationRire label.
The tires installed on your vehicle when it was new had
a Tire Performance
Criteria Specification
(TPC Spec) number on each tire’s sidewall. When you
get new tires, get ones with that same TPC Spec number. That way, your
vehicle will continue
to have tires that are designed to give proper
endurance, handling, speed rating, traction, ride and other things during
normal service on your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by a
“MS” (for mud and snow).
If you ever replace your tires with those not having
a TPC Spec number,
make sure they are
the same size, load range, speed rating and construction
type (bias, bias-belted or radial) as your original tires.
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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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