change wheel GMC SIERRA 2008 User Guide
[x] Cancel search | Manufacturer: GMC, Model Year: 2008, Model line: SIERRA, Model: GMC SIERRA 2008Pages: 578, PDF Size: 6.47 MB
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Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
You approach things faster and you have less time
to scan the terrain for obstacles.
You have less time to react.
You have more vehicle bounce when you drive over
obstacles.
You will need more distance for braking, especially
since you are on an unpaved surface.
{CAUTION:
When you are driving off-road, bouncing and
quick changes in direction can easily throw
you out of position. This could cause you to
lose control and crash. So, whether you are
driving on or off the road, you and your
passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain
and its many different features. Here are some things to
consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow,
or ice. Each of these surfaces affects the steering,
acceleration, and braking of your vehicle in different
ways. Depending upon the kind of surface you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction, and longer braking
distances.
Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut, or bump can startle
you if you are not prepared for them. Often these
obstacles are hidden by grass, bushes, snow, or even
the rise and fall of the terrain itself. Here are some
things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
There is more discussion of these subjects later.
Will you have to stop suddenly or change direction
quickly?
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Driving in Mud, Sand, Snow, or Ice
When you drive in mud, snow, or sand, your wheels will
not get good traction. You cannot accelerate as
quickly, turning is more difficult, and you will need longer
braking distances. If your vehicle has four-wheel
drive, seeFour-Wheel Drive on page 2-36for transfer
case mode selection.
It is best to use a low gear when you are in mud — the
deeper the mud, the lower the gear. In really deep
mud, the idea is to keep your vehicle moving so you do
not get stuck.
When you drive on sand, you will sense a change in
wheel traction. But it will depend upon how loosely
packed the sand is. On loosely packed sand, such as
on beaches or sand dunes, your tires will tend to
sink into the sand. This has an effect on steering,
accelerating, and braking. Drive at a reduced speed and
avoid sharp turns or abrupt maneuvers.Hard packed snow and ice offer the worst tire traction.
On these surfaces, it is very easy to lose control.
On wet ice, for example, the traction is so poor that you
will have difficulty accelerating. And if you do get
moving, poor steering and difficult braking can cause
you to slide out of control.
{CAUTION:
Driving on frozen lakes, ponds, or rivers can
be dangerous. Underwater springs, currents
under the ice, or sudden thaws can weaken the
ice. Your vehicle could fall through the ice and
you and your passengers could drown. Drive
your vehicle on safe surfaces only.
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6. Adjust the Trailer Gain to just below the point of
trailer wheel lock-up, indicated by trailer wheel
squeal or puffs of tire smoke when a trailer
wheel locks.
Trailer wheel lock-up may not occur if towing a
heavily loaded trailer. In this case, adjust the Trailer
Gain to the highest allowable setting for the
towing condition.
7. Re-adjust Trailer Gain any time vehicle loading,
trailer loading or road surface conditions change
or if you notice trailer wheel lock-up at any
time while you are towing
Other ITBC Related DIC Messages
In addition to displaying TRAILER GAIN and TRAILER
OUTPUT through the DIC, trailer connection and
ITBC system status is displayed in the DIC.
TRAILER CONNECTED – This message will be brie y
displayed when a trailer with electric brakes is rst
connected to the vehicle. This message will
automatically turn off in about ten seconds. The driver
can also acknowledge this message before it
automatically turns off.CHECK TRAILER WIRING – This message will be
displayed if:
1. The ITBC system rst determines connection to a
trailer with electric brakes and then the trailer
harness becomes disconnected from the vehicle.
If the disconnect occurs while the vehicle is
stationary, this message will automatically turn off in
about thirty seconds. This message will also turn
off if the driver acknowledges this message off or if
the trailer harness is re-connected.
If the disconnect occurs while the vehicle is moving,
this message will continue until the ignition is
turned off. This message will also turn off if the
driver acknowledges this message off or if the trailer
harness is re-connected.
2. There is an electrical fault in the wiring to the
electric trailer brakes. This message will continue as
long as there is an electrical fault in the trailer
wiring. This message will also turn off if the driver
acknowledges this message off.
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