What is a CV Axle and What Does it Do?
What is a CV Axle and What Does it Do?
Your vehicle is made up of a large number of components that all work together to get you safely to your destination. Many of these parts you may be familiar with like your brakes and tires, others may be not as clear. In this article we are going to talk about CV axles, what they are, what they do and how to know if you may have an issue that needs attention. Hopefully after reading this article, you will have an increased understanding of your vehicle’s components and what it means when you are told “You have a bad CV axle.”
What is a CV Axle?
A CV axle, or Constant Velocity axle, serves as a critical link in your vehicle’s drivetrain system. This component transfers power from your transmission (or differential) to your wheels while accommodating the up-and-down motion of your suspension and the turning of your wheels.
The typical CV axle consists of three main components:
- An inner joint that connects to the transmission or differential
- A solid shaft running between the joints
- An outer joint that connects to the wheel hub
CV axles are most commonly found in front-wheel-drive vehicles, where they must not only transfer power, but also allow for steering. However, they’re also used in many all-wheel-drive and rear-wheel-drive vehicles with independent suspension systems.
What makes CV axles different from older universal joints is their ability to maintain a constant velocity transfer even at extreme angles. Traditional universal joints slow down and speed up slightly as they rotate at an angle, causing vibration and wear. CV joints eliminate this problem, providing smoother operation and greater durability.
How CV Axles Work
The CV axle’s unique ability is to perform multiple functions simultaneously. Its primary function is to transfer the rotational power from your engine and transmitting the power to your wheels from its connection to a transmission or differential.
However, unlike a simple straight axle, CV axles must accommodate complex movements. When you turn your steering wheel, your front wheels pivot on an angle. A CV axle maintains constant rotational speed even as these angles change, ensuring smooth power delivery without binding or jerking.
Additionally, as your vehicle travels over bumps and dips in the road, your suspension system moves up and down. The CV axle must allow for this vertical movement while continuing to transfer power efficiently. This is particularly important during acceleration, when significant torque is being applied through the axle.
Think of the CV axle as a flexible connection that can bend and adjust while still maintaining its primary function of transferring rotational energy. This flexibility comes from the unique design of the constant velocity joints, which use ball bearings in special tracks to maintain consistent motion regardless of the operating angle.
Signs of a Failing CV Axle
Recognizing the symptoms of a failing CV axle early can save you from more expensive repairs down the road. Here are the most common warning signs to watch for:
- Clicking noises when turning: This is perhaps the most telltale sign of a CV axle problem. If you hear a clicking or popping sound that gets louder when making sharp turns (particularly when accelerating through a turn), it likely indicates a problem with the outer CV joint.
- Grease leakage around wheel area: CV joints are protected by rubber boots filled with grease. If these boots crack or tear, you may notice dark grease splattered on the inside edge of your tire or on nearby suspension components. This is a serious warning sign, as once the joint loses its lubrication, failure will follow quickly.
- Vibrations while driving: A damaged CV axle can cause vibrations that you will feel through the floor or steering wheel, especially during acceleration. These vibrations may increase with vehicle speed and can sometimes be mistaken for tire balance issues.
Consequences of Driving with a Bad CV Axle
Continuing to drive with a failing CV axle can lead to several serious consequences:
- Reduced vehicle control: A severely worn or damaged CV axle can affect your ability to control your vehicle, particularly during acceleration or when navigating turns.
- Potential for complete drivetrain failure: If a CV joint fails completely while driving, it can cause the axle to break. This will immediately disable your vehicle, potentially leaving you stranded in an inconvenient or dangerous location.
- Damage to related components: A failing CV axle doesn’t exist in isolation. The vibration and irregular movement it creates can damage your transmission, differential, wheel bearings, and other drivetrain components, compounding your repair costs.
- Safety concerns: Any component failure that affects your ability to control your vehicle presents a safety risk to you, your passengers, and others on the road.
Your vehicle’s CV axles may not be as well-known as the engine or transmission, but they perform an equally essential role in your car’s operation. Understanding what they do and recognizing the signs of failure can help you address problems early, saving money and preventing potential roadside breakdowns.
Axle & Drivetrain Service at Matson Point S in Riverton, Utah
At Matson Point S Tire & Service in the Salt Lake Valley, we specialize in comprehensive drivetrain services, including CV axle inspection and replacement. Our experienced technicians use quality parts and proper installation techniques to ensure your vehicle performs safely and reliably.
Call our Riverton location or schedule your appointment online today to ensure your vehicle’s drivetrain is in proper operating condition.