What Is a Car Axle?

July 22,2015

transaxle1Axles are a very important part of your vehicle. Without them, your wheels will not move, and, safety-wise, a sound axle is as vital as good brakes or tires. People understand that without functional brakes, tires, engines, or steering systems, cars will not function or function safely, but most people are unaware of the crucial value a car’s axle has.

In its most basic form, a car axle is a rod or a shaft that is spun in order to move a vehicle’s wheels. Think of a railroad car or a Radio Flyer wagon. The axle is the bar that connects the wheels. It also holds the weight of the car or wagon. On a motorized vehicle, the axle transfers engine power and torque from the transmission to the drive wheels. Contemporary front-wheel-drive vehicles often will combine the transmission and the front axle into what is called a transaxle. On vehicles with rear-wheel drive, the engine connects to a drive shaft, and the drive shaft turns the drive axle in the back of the vehicle.

Most modern cars have a split axle with universal joints between two half axles. A constant velocity (CV) joint connects each of these to a wheel.  This allows for each wheel to have independent suspension, pivot when making turns, and turn at different speeds, improving tire traction and extending tire life.

A broken axle is often the result of overloading a vehicle, a bad carrier bearing, or even just an unfortunate pothole experience. If you hear rumbling or feel vibrating when you accelerate or turn your car, this is a sign of an axle going bad or able to break. If your axle is broken you will not be able to drive your car. It’s unlikely that you won’t notice your axle going bad, however. It’s usually accompanied by loud clicking or banging noticeable when your car shifts gears or the previously mentioned rumbling or vibrating with turning or accelerating.

If you notice any of these signs, you should get your car to a capable mechanic so he can evaluate the axle. You should not drive a car with a broken axle, although, of course, once it has broken at the universal joint, you will not be able to. Pushing down on the accelerator will just rev the engine, it will not make the car go.

If you think your axle is going bad or have any other questions about maintaining the safety and functioning of your vehicle, contact Veenstra’s Garage today. We’d be glad to answer any questions or examine your vehicle in person.