1995 GMC SIERRA tire change

Anti-Lock Brakes (ABS)
Your vehicle has an advanced electronic braking system that can help you
keep it under control. When you start your vehicle and begin to drive away,
you may hear a momentary motor or clicking noise. This is the
ABS system
testing itself.
Here's how anti-lock works. Let's say the road is wet. You're driving safely.
Suddenly an animal jumps out
in front of you.
You slam on the brakes. Here's what happens with ABS.
A computer senses that wheels are slowing down. If one of the wheels is
about
to stop rolling, the computer will separately work the brakes at each
front wheel and at the rear wheels. The anti-lock system can change the
brake pressure faster than any driver could. The computer is programmed to
make the most
of available tire and road conditions.
You can steer around the obstacle while braking hard.
As you brake, your computer keeps receiving updates on wheel speed and
controls braking pressure accordingly.
4-6
ProCarManuals.com

Remember: Anti-lock doesn’t change the time you need to get your foot up
to the brake pedal. If you get too close to the vehicle in front of you, you
won’t have time
to apply your brakes if that vehicle suddenly slows or
stops. Always leave enough room up ahead to stop, even though
you have
anti-lock brakes.
To Use Anti-Lock
Don’t pump the brakes. Just hold the brake pedal down and let anti-lock
work for you. You may feel the brakes vibrate, or you may notice some
noise, but this is normal. On vehicles
with four-wheel drive, your anti-lock
brakes work at all times
- whether you are in two-wheel drive or
four-wheel drive.
Braking in Emergencies
Use your anti-lock braking system when you need to. With anti-lock, you
can steer and brake at the same time. In many emergencies, steering can
help you more than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine stops or the system is
not functioning, you can steer but it will take much more effort.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control’’ accidents mentioned on the news happen
on curves. Here’s why:
Experienced driver or beginner, each of
us is subject to the same laws of
physics when driving on curves. The traction of the tires against the road
surface makes
it possible for the vehicle to change its path when you turn
the front wheels.
If there’s no traction, inertia will keep the vehicle going in
the same direction. If you’ve ever tried to steer
a vehicle on wet ice, you’ll
understand this.
The traction
you can get in a curve depends on the condition of your tires
and the road surface, the angle at which the curve is banked, and your
speed. While you’re
in a curve, speed is the one factor you can control.
4-7
ProCarManuals.com

Try not to pass more than one vehicle at a time on two-lane roads.
Reconsider before passing the next vehicle.
0 Don’t overtake a slowly moving vehicle too rapidly. Even though the
brake lights are
not flashing, it may be slowing down or starting to turn.
If you’re being passed, make it easy for the following driver to get
ahead
of you. Perhaps you can ease a little to the right.
Loss of Control
Let’s review what driving experts say about what happens when the three
control systems (brakes, steering and acceleration) don’t have enough
friction where the tires meet the road
to do what the driver has asked.
In any emergency, don’t give up. Keep trying
to steer and constantly seek an
escape route or area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle. Defensive drivers avoid
most skids by taking reasonable care suited
to existing conditions, and by
not “overdriving” those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s three control systems.
In the braking skid your wheels aren’t rolling. In the steering or cornering
skid, too much speed or steering in
a curve causes tires to slip and lose
cornering force. And
in the acceleration skid too much throttle causes the
driving wheels to spin.
A cornering skid and an acceleration skid are best handled by easing your
foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot
off the accelerator pedal and
quickly steer the way you want the vehicle
to go. If you start steering
quickly enough, your vehicle may straighten out. Always be ready for
a
second skid if it occurs.
Of course, traction is reduced when water, snow, ice, gravel, or other
material is on
the road. For safety, you’ll want to slow down and adjust your
driving to these conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and vehicle control more
limited.
While driving on a surface
with reduced traction, try your best to avoid
sudden steering, acceleration. or braking (including engine braking
by
shifting to a lower gear). Any sudden changes could cause the tires to slide.
You may not realize the surface is slippery until your vehicle
is skidding.
Learn
to recognize warning clues - such as enough water, ice or packed
snow
on the road to make a “mirrored surface” - and slow down when you
have any doubt.
Remember:
Any anti-lock brake system (ABS) helps avoid only the braking
skid.
4-13
ProCarManuals.com

Stalling on an lncline
If your vehicle stalls when you’re crossing an incline, be sure you (and your
passengers) get out on the uphill side,
even if the door there is harder to
open.
If you get out on the downhill side and the vehicle starts to roll over,
you’ll be right in its path.
If you have to walk down the slope, stay out of the path the vehicle will take
if it does roll over.
1 A CAUTION:
Getting out on the downhill (low) side of a vehicle stopped across
an incline is dangerous.
If the vehicle rolls over, you could be
crushed or killed. Always get out on the uphill (high) side of the
vehicle and stay well clear
of the rollover path.
Driving In Mud, Sand, Snow, Or Ice
When you drive in mud, snow or sand, your wheels won’t get good traction.
You can’t accelerate
as quickly, turning is more difficult, and you’ll need
longer braking distances.
It’s best
to use a low gear when you’re in mud - the deeper the mud, the
lower
the gear. In really deep mud, the idea is to keep your vehicle moving
so you don’t get stuck.
When you drive on sand, you‘ll sense
a change in wheel traction. But it will
depend upon how loosely packed the sand
is. On loosely packed sand (as on
beaches or sand dunes) your tires will tend to sink into the sand. This has an
effect on steering, accelerating, and braking.
You may want to reduce the air
pressure in your tires slightly when driving
on sand. This will improve
traction.
4-21
ProCarManuals.com

To wing Your Vehicle
Try to have your GM dealer or a professional towing service tow your
vehicle. They can provide the right equipment and know how to tow
it
without damage.
If your vehicle has been changed since
it was factory-new. by adding such
things like fog lamps, aero skirting,
or special tires and wheels, these things
could be damaged during towing.
Before you do anything,
turn on the hazard warning flashers.
When you call, tell the towing service:
0 That your vehicle has rear-wheel drive, or that it has the four-wheel
drive option.
The make, model, and year of your vehicle.
0 Whether you can move the shift lever for the transmission and transfer
case,
if you have one.
If there was an accident. what was damaged.
A CAUTION:
To help avoid injury to you or others:
Never let passengers ride in a vehicle that is being towed.
0 Never tow faster than safe or posted speeds.
0 Never tow with damaged parts not fuIly secured.
0 Never get under your vehicle after it has been lifted by the
tow truck.
0 Always use separate safety chains on each side when towing a
vehicle.
0 For pickups (except cab chassis models), use T-hooks on front
. of vehicle, J-hooks on rear.
For cab chassis models, use J-hooks on front and rear of
vehicle.
When your vehicle is being towed, have the ignition key off. The steering
wheel should be clamped
in a straight-ahead position, with a clamping
device designed for towing, service.
Do not use the vehicle’s steering
column lock for this. The transmission and transfer case, if
you have one,
should be
in NEUTRAL (N) and the parking brake released.
5-7
ProCarManuals.com

Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster
to provide more air to cool the engine. In most every day
driving conditions the fan is spinning slower and the clutch is
not fully
engaged. This improves fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside temperatures, the fan
speed increases as the clutch more fully engages.
So you may hear an
increase
in fan noise. This is normal and should not be mistaken as the
transmission slipping or making extra shifts.
It is merely the cooling system
functioning properly. The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the
fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out
of a tire, it’s much more likely to
leak out slowly. But if you should ever have a “blowout,” here are a few tips
about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot
off the accelerator pedal and grip the
steering wheel firmly, Steer
to maintain lane position, then gently brake to a
stop well out of
the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your
foot from the accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well
off the road if
possible.
If a tire goes flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
5-25
ProCarManuals.com

Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driving slowly to a
level place. Turn on your hazard warning flashers.
A. Flat Tire
B. Blocked Tire
The following steps will tell
you how to use the jack and change a tire.
The equipment you’ll need
is behind the passenger’s seat. Turn the wing nut
counterclockwise and remove the jack cover, if there is one.
Your spare tire
is stowed under the truck bed, at the
rear.
5-26
ProCarManuals.com

Front rosluon Rear Position
With UP on the ratchet facing you, raise the vehicle by rotating the ratchet
and wheel wrench clockwise. Raise the vehicle
far enough off the ground so
there is enough room for the spare tire to fit.
Remove
all the wheel
nuts and take
off the
flat tire,
A CAUTION:
Rust or dirt on the wheel, or on the parts to which it is fastened,
can make the wheel nuts become loose after a time. The wheel
could come
off and cause an accident. When you change a wheel,
remove any rust or dirt from the places where the wheel attaches
to the vehicle. In an emergency, you can use a cloth or a paper
towel
to do this; but be sure to use a scraper or wire brush later,
if you need to, to get all the rust or dirt off.
5-35
ProCarManuals.com