Throughout this site we use many technical terms, and given the breadth of readership our site enjoys, sometimes we are remiss and incorrectly assume everyone knows what we are referring to. For those that do not, here are some explanations of the technical terms use.
The engine, the clutch and the transmission form one unit at the front end of the car. The differential, the rear wheels, and their supporting axles form another unit at the rear end of the car. A link is needed to connect these two units. The link that is used to connect the front unit with the rear unit is called the propeller shaft. Propeller shafts may be either solid or hollow in construction, but must be strong enough to withstand the turning and twisting strains of high-speed operation.
Since the driving axle of the automobile is generally set somewhat lower that the transmission, the propeller shaft must run down at an angle to meet the rear axle. In some modern cars, like the Rover and Studebaker, it has an unusual joint in the centre mounting. One end of the propeller shaft is attached to the transmission shaft which is mounted rigidly, but the other end is connected to the rear axle which is constantly moving up and down as the wheels follow the contours of the road.