A diagram showing a side and underside view of an 18-wheeler semi-trailer truck with an enclosed cargo space. The underside view shows the arrangement of the wheels, and in blue, the axles, drive shaft, and differentials.
Diagram: H Padleckas and Ju gatsu mikka
The numbered parts are:
- tractor unit
- semi-trailer (detachable)
- engine compartment
- cabin
- sleeper (not present in all trucks)
- air dam
- fuel tanks
- fifth-wheel coupling
- enclosed cargo space
- landing gear (legs for when semi-trailer is detached)
- tandem axles
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