Motor Musings

Greetings fellow auto enthusiasts and welcome to the first of a series of automotive articles in which we here at Motor Musings (by “we” I mean “I”) will attempt to - at random intervals - explain one part of a car, truck, boat, or plane for each letter of the alphabet.

For no particular reason I chose to start with the letter ‘A’. After long consideration (at least five seconds) I decided to enlighten the masses (that’s you) about axles.

In it’s simplest form, an axle is just a shaft on which to mount a couple of wheels. Think about the little red wagon you had as a kid. The metal bar that ran between the wheels was the axle. This works fine for the simplest of vehicles (heavy duty trucks still use something similar), but for a better ride we need something a bit more complex.

One of the biggest problems with solid axles is that anything that affects one wheel directly affects the other wheel on that axle. If your right front wheel drops into a pothole, your left front wheel will no longer be perpendicular to the roadway. In a curve this could be disastrous - especially if you were driving near the limits for that curve.

Enter the independent suspension. Early Volkswagen Beetles used a simple independent rear suspension (IRS), called a swing axle. It improved on the solid axle by preventing the movement of one wheel from affecting the other, however the moving wheel still exhibits camber changes. That is, as the wheel moves up and down it deviates from perpendicular to the road.

Today’s independent axles have improved upon this tremendously. Many hours of calculations go into the design of the suspension’s pivot points in order to keep the wheel firmly planted to the road under all foreseeable circumstances.

To summarize:

As usual, if you have anything to add, let us know in the comments.

Cheers,
Dorri

axles, Autos A-Z