What does my car’s CV joint do?

The CV (constant velocity) joint, also known as a CV axle or driveshaft, plays a crucial role sending power from the engine to the wheels. This allows for smooth and continuous rotation. CV joints are primarily found in front-wheel drive vehicles, although they can also be present in some all-wheel drive and rear-wheel drive vehicles.

The main benefits that a CV joint provides are as follows:

  • Power transmission: The CV joint transfers torque from the engine to the wheels. As the engine generates rotational power, it is transmitted through the transmission or transaxle to the CV joint. The CV joint then transfers this power to the wheels, allowing the vehicle to move forward or backward.
  • Flexibility and range of motion: The CV joint allows for flexibility and a wide range of motion in the drive axle. As the wheels turn and the suspension system moves, the CV joint accommodates these movements by maintaining a constant velocity and angle. This flexibility is crucial in maintaining a smooth transfer of power, especially during steering and suspension articulation.
  • Compensation for axle length changes: In front-wheel drive vehicles, the CV joint compensates for changes in axle length as the suspension moves up and down. This is necessary because the distance between the engine and the front wheels changes as the suspension compresses or extends. The CV joint allows for this length variation while maintaining a consistent speed of rotation.
  • Absorption of road irregularities: The CV joint helps to absorb and dampen vibrations and shocks caused by road irregularities, such as bumps and potholes. It does this by using a combination of bearings and grease to provide a smooth rotation and minimize the transmission of vibrations to the vehicle’s chassis.


Do CV joints and boots need replacement?

Your CV joint acts as a direct link between your engine and wheels. Because of this, the joint will be subject to powerful forces. Over time, these forces will cause your CV joint to wear out. Once the joint wears out, it will need replacing.

The CV boot will need replacing if it cracks. This is because it will allow the CV Joint grease to come out of the joint. A split CV Joint boot also exposes key components of the joint such as the CV joint bearings and inner race, putting them at risk of damage by dirt, stones and dust wearing them out quickly.


Symptoms of CV joint / boot damage:

  1. Clicking or popping noises while turning: One of the most noticeable signs of a damaged CV joint is a clicking or popping sound when making turns, especially at low speeds. This noise often gets louder when the joint is under more stress, such as when turning tightly or accelerating.
  2. Vibrations during acceleration: If you feel strong vibrations or shuddering sensations coming from the front wheels during acceleration, it could indicate a damaged CV joint. The vibrations may be more pronounced during higher speeds or under heavy load.
  3. Grease leakage: CV joints are protected by rubber boots that seal in the lubricating grease. If these boots become damaged or torn, grease can leak out, leaving the joint vulnerable to contamination and accelerated wear. Inspect the CV joint boots for signs of grease leakage or cracks.
  4. Axle boot damage: The CV joint is covered by a rubber or plastic boot that protects it from dirt, debris, and moisture. If you notice any tears, cracks, or damage to the axle boot, it increases the risk of debris entering the joint and causing damage.
  5. Difficulty steering: A damaged CV joint can affect the vehicle’s maneuverability, making it more difficult to steer smoothly, especially during turns. You may experience a “binding” sensation or a sense that the wheels are not responding as they should.


We offer CV joint and boot repair/replacement in Hamilton.

At Grimmer Motors, we can inspect, repair and replace components of your axle shaft assembly. We have the correct tools and a range of methods to fit new CV Joints and Boots. We are happy to help with all CV joint and boot problems. For reliable, honest mechanical services, give us a call.