SAND
The major problem sand presents is to gain traction
without digging in. Sand can be stabilized with a large
volume of water but loosens as soon as it dries out.
Often, tires spin and dig into the sand rapidly which
causes a jerking motion in the drive line.
NOTE: This jerking motion can cause severe
damage to axles, differentials, and propeller shafts.
All-wheel drive vehicles have less difficulty, but they
consume considerable power.
Should you have to operate in sand, there are some
actions you can take to help you out when a winch is not
available. Partially deflate your tires; this gives your
tires a wider footprint for traction. You can use mats of
brush, wire, grass, lumber or anything that can bridge
over and allow you to spread the load of your vehicle
over a larger area.
CROSS-COUNTRY
Driving cross-country can produce many problems.
Should you have to drive cross-country, it is best to have
someone walk in front of your vehicle to look for holes,
stumps, and ditches that may damage your vehicle.
Proceed slowly and use the lowest gear possible. Avoid
wet, marshy areas if possible because a marsh will crust
over and break through if you drive over it. When it
breaks through, there is little you can do but call for
assistance to be towed.
Watch out for stumps, rocks, or anything on which
you may get high center. Sometimes it is better to keep
your tires on large rocks and go over them, rather than
straddle them. Stumps may be cut off for your vehicle
to clear.
DRIVING HOURS
Driving hours are regulated by the U.S. Department
of Transportation, Code of Federal Regulations, Title
49. These regulations are reflected in the Federal Motor
Carrier Safety Regulations Pocketbook, ORS-7A. You
are restricted to drive no longer than 10 hours in a
15-hour period after 8 hours off duty. You, the operator,
are responsible for the safe operation of your vehicle.
As a safety measure, an operator should take breaks
or rest stops when becoming fatigued or sleepy. After
parking the vehicle, get out and walk around to stretch
your muscles. Rest stops are especially important on a
long trip requiring many hours of driving.
WARNING
Extended periods of driving often results in
driver fatigue. Physical and mental fatigue
brought on by extended periods of time behind
the wheel is a frequent problem encountered by
operators. If operators are exhausted, they may
doze at the wheel and lose control of the vehicle,
resulting in a serious or fatal mishap.
MOUNTAIN DRIVING
The force of gravity plays a major role in mountain
driving. If you have a heavy load or a fully loaded bus,
you must select lower gears to climb the hills. When
going down steep hills, the pull of gravity speeds you
up. You must go slow so your brakes can hold you back
without overheating. If the brakes become too hot, they
may start to fade. This means that you have to apply
them harder and harder to get the same stopping power.
When the brakes continue to be used hard, they continue
to fade until you cannot slow down or stop at all.
Use of Gears
No matter what size of vehicle you are descending
long, steep grades in, going too fast can cause your
brakes to fail. Lower gears allow engine compression
and friction to help slow the vehicle. This is true whether
you have an automatic or a manual transmission.
When you are operating a large vehicle with a
manual transmission or a fully loaded bus, do not wait
until you have started down a hill to shift down. You
could get hung up in neutral and find yourself coasting,
which is not only illegal but is also dangerous.
Remember: Choose the right gear before starting down
a hill.
For older trucks, the rule of thumb for choosing
gears is to use the same gear going down a hill that you
would use to climb the hill. New trucks have low friction
parts and streamlined shapes for fuel economy and often
have more powerful engines. This allows them to go up
hills in higher gears. They also have less friction and air
drag to hold them back when going down a hill. For this
reason, operators of newer trucks often have to use
lower gears going down a hill than needed to go up the
hill.
Proper Braking
When going downhill, brakes tend to heat up. When
engaged, the brake pads and shoes rub against the brake
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