<P> In rear - wheel drive cars and trucks, the engine turns a driveshaft (also called a propellor shaft or tailshaft) which transmits rotational force to a drive axle at the rear of the vehicle . The drive axle may be a live axle, but modern rear wheel drive automobiles generally use a split axle with a differential . In this case, one half - axle or half - shaft connects the differential with the left rear wheel, a second half - shaft does the same with the right rear wheel; thus the two half - axles and the differential constitute the rear axle . </P> <P> Some simple vehicle designs, such as leisure go - karts, may have a single driven wheel where the drive axle is a split axle with only one of the two shafts driven by the engine, or else have both wheels connected to one shaft without a differential (kart racing). However, other go - karts have two rear drive wheels too . </P> <P> A dead axle, also called a lazy axle, is not part of the drivetrain, but is instead free - rotating . The rear axle of a front - wheel drive car is usually a dead axle . Many trucks and trailers use dead axles for strictly load - bearing purposes . A dead axle located immediately in front of a drive axle is called a pusher axle . A tag axle is a dead axle situated behind a drive axle . Dead axles are also found on semi trailers, farm equipment, and certain heavy construction machinery serving the same function . On some vehicles (such as motorcoaches), the tag axle may be steerable . In some designs the wheels on a lazy axle only come into contact with ground when the load is significant, thus saving unnecessary tire wear . </P> <P> Some dump trucks and trailers may be configured with a lift axle (also known as an airlift axle or drop axle), which may be mechanically raised or lowered . The axle is lowered to increase the weight capacity, or to distribute the weight of the cargo over more wheels, for example to cross a weight restricted bridge . When not needed, the axle is lifted off the ground to save wear on the tires and axle, and to increase traction in the remaining wheels . Lifting an axle also alleviates lateral scrubbing of the additional axle in very tight turns, allowing the vehicle to turn more readily . In some situations removal of pressure from the additional axle is necessary for the vehicle to complete a turn at all . </P>

Where is the axle located on a car