Lesson l/Learning Event 1
FIGURE 2. FIFTHWHEEL STEERING.
ACKERMAN STEERING
The fifthwheel method of steering is not suitable for steering a modern car
or truck. The vehicle chassis would have to be too high off the ground to
provide clearance for the front wheels. Cars and trucks use a different
front wheel arrangement. It is called the Ackerman steering method.
With this arrangement, the axle is held at a right angle to the vehicle
frame and cannot pivot. The wheels change from the straightahead position
independently on separate pivot pins or knuckle pivots at the ends of the
axle.
We will be discussing only the Ackerman steering method during the rest of
this lesson, so let's clarify the terms that we will be using in regard to
wheel movements with this method. When we say "the wheels pivot," we mean
that they are changed in relation to the straightahead position when making
a right or left turn. When we say "the wheels rotate," we mean that they
turn on their spindles as the vehicle rolls forward or backward.
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