Practice question

What is the function of the sliding fifth wheel on a heavy commercial truck tractor?

To allow the driver to steer the trailer from the cab
To shift weight distribution between the tractor drive axles and steer axle, and to adjust clearance between tractor cab and trailer nose
To lower the trailer to the ground during loading
To lock the trailer wheels when parked

Answer: B — To shift weight distribution between the tractor drive axles and steer axle, and to adjust clearance between tractor cab and trailer nose

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