Bad CV Joint Symptoms | What is a Constant Velocity Joint?

For a better understanding of the Constant Velocity joint or CV joint, it is necessary to know about the axle of your car first. The axle is something that helps the car wheel to move and is one of the important mechanical parts of your car.

To send motion from the transmission to the wheels of the vehicle, the front wheel needs a special kind of axle. This special axle is known as the CV axle. The CV joint connects wheels with axles as well as with transmission.

The Constant Velocity joint plays its role in transferring the power of the engine to the wheels. Consequently, CV axles are spined by the engine, and wheels being connected to the axle let the vehicle move further.

What is CV Joint?

Constant Velocity or CV joint is a mechanical joint that lets the drive shaft to deliver power through multiple angles at a constant speed without a significant increase in inertia or friction.

CV Joint

As mentioned before, CV joints are known by multiple names; we also call them homokinetic joints. The CV joints are most commonly used in front-wheel drive cars. The latest rear-wheel drive vehicles having independent rear suspension contain CV joints on the drive shaft and at the finishing point of rear axle half shafts.

In simple words, they are components of the driveshaft having the task of linking the transmission to the wheels of the vehicle.

As a matter of fact, rear-wheel drive cars, four-wheel drive cars, and trucks also contain CV joints.

Types of Constant Velocity Joints

There are two types of CV joints:

  1. Inner joint: It links the transmission to the axle
  2. Outer joint: It links the vehicle axle to the wheel.

Function of CV Joint

The main function of the CV joint in a vehicle is to send power from the transmission to the wheels of the vehicle. Power is transferred with the least friction at consistent velocity, or we can say that regardless of the steering wheel angle, the power from the engine of the vehicle is shifted smoothly to the vehicle wheels.

Function of CV Joint

Symptoms of a Bad CV Joint 

The following are the most common symptoms of bad CV joints:

  1. Vibration
  2. Getting bounce while driving
  3. Loud noises while turning the vehicle
  4. Grease leakage
  5. Knocking sounds while moving

1) Vibrations

A faulty constant velocity joint starts vibrating when you drive your car. In such conditions, it is difficult for the faulty CV joints to retain the balance of the vehicle while driving. So, the condition will get worse after increasing the acceleration of the vehicle.

Excessive vibration can make the vehicle difficult to control and affect overall driving comfort. It means damaged CV joints impacting the whole driving experience and making it unsafe. The only solution to fix this all is to let CV joints check and replace them.

2) Getting Bounce While Driving

If you are getting bouncy drive even on a carpeted road, it’s a sign of a faulty CV joint. So, it’s better to check it by going to the nearby service center.

3) Loud Noises while Turning the Vehicle

If your vehicle generates popping or clicking noises as you turn the steering wheel, it is one of the major symptoms of a damaged CV joint. If you want to check this, you can go through the following three steps:

  • Reverse the gear
  • Turn the wheels to the one side of the vehicle
  • Press the gas pedal

As you move the vehicle in a circular direction, it’s better to check and clear the area around you. You must replace the CV joints or maybe the whole shaft assembly if you find the popping sound getting worse while moving back in a circular direction.

4) Grease Leakage

If you find the grease because of a tear or small crack near the sides of the wheels, it can be a sign of bad CV joints. The presence of tan-colored grease on the rim or the inner side of the wheels shows the major problem in the CV joints of the vehicle.

5) Knocking sounds While Moving

Excessively used CV joints produce knocking sounds while moving. This knocking sound is normally produced from the inner joint of a front-wheel drive car. 

In the case of rear-wheel drive, it originates through the outer or inner joint. Differential gears can also be the reason for producing this knocking sound.

  1. You can do a self-diagnostic test to check for a bad CV joint.
  2. Put on your car in reverse and accelerate the car.
  3. Now decelerate it.
  4. Switch back and forth in acceleration and deceleration.
  5. Try to listen to that knocking sound if it is here or not. If yes, then your car has a bad CV joint.

Read More: Signs of a bad Axle

CV Joint Replacement Cost

The cost of the CV joint replacement depends on which type of axle you are replacing and the labor cost. It can be a double or a single axle according to the damage.

Replacement of a constant-velocity joint with a double axle will cost you about twice as expensive as a single axle. With all parts, the cost for the replacement of a CV joint with a double axle can be from $140 to $410, and for a single axle, it will be around $70 to $205.

CV Boot Replacement Cost

CV boot replacement cost is low compared to CV joint replacement. If you caught the damaged CV boot early, replacing the damaged boot and repacking the CV joint with fresh grease is enough. The average replacement cost of the CV joint boot is from $170 to $355.

How to test a CV Joint

Following are the steps you must follow to test the CV joints of your car by yourself:

  • Internally examine your Constant Velocity joint and search for any worn-out or damaged parts. You can use the torchlight for a clear view.
  • Try to find grease on the joints.
  • With the help of your thumb, hold the CV axle and try to move it in either direction. If your car’s joint is healthy, you will notice a smooth slight movement in the axle.
  • Take your car for a test drive in a large field and drive it in the same direction in the form of circles. You can change the steering wheel to another direction and observe the sound.
  • If you hear any kind of clicking sound while driving, there is a possibility that your car is having a Constant Velocity joint issue.
  • But if the sound is smooth, then your car’s CV joint is perfect.

FAQ Section

How long a CV joint lasts?

A CV joint can usually last from 71,000 to 131,000 miles, but it is highly recommended to check CV joints frequently.

Can a bad CV joint affect the transmission?

Yes. Constant velocity joint and transmission of your vehicle are interlinked. Therefore, joints highly affect the transmission system of your vehicle. Vibrations and bumpy drives can result from a bad transmission due to a bad CV joint in your car. With prolonged vibrations, bearings, brushes, and other parts of your car’s transmission can be damaged.

What happens when inner CV joint fails?

Inner CV joint failures are rare. One of the symptoms of a failed inner CV joint is lateral (side-to-side) shaking or vibration during acceleration. A worn-out inner CV joint may also cause clunking when shifting from Drive to Reverse or from accelerating to decelerating.

Can I drive with a bad CV Axle?

Yes, you can drive with a bad CV axle for a short time if there is no major symptom. But if it affects steering input or creates issues with the suspensions, you should stop instantly.  

What causes CV joint damage?

Shock loading is one of the major causes of a damaged CV joint. When a spinning wheel is lifted from the ground and then lands forcefully back to the ground, the protective CV boot gets damaged, resulting in grease leakage.

How many CV joints does a car have?

A car has two CV joints: the inner joint and the outer joint. The inner joint attaches the transmission to the axle, and the outer joint attaches the axle to the wheel.

What will happen if my car hits a pothole?

An abrupt hit to any pothole can rock your car’s whole suspension system and results in damaged shocks and struts. Detection of this damage to the shocks and struts can be tricky sometimes. Visibly a flat tire and a bent rim can be an instant uncomfortable result of hitting a pothole.

What can cause a CV axle to fail?

CV axle can fail due to damaged or broken boot. That is usually done by the falling bearings in a joint.

Is CV boot replacement and CV joint replacement both are same?

No, they both are different. In CV boot replacement, the technician only replaces the damaged boot of the CV joint and repacks the joint with fresh grease, but in the case of CV joint replacement, the whole joint of your car got replaced. CV boot replacement is cheaper than CV joint replacement.

What is the CV joint dangerous noise

Any clunking, popping, or clicking noise that emanates from your car’s front wheel may signify that there’s a problem with your CV joint. The noises usually become more pronounced when you turn your steering wheel. If possible, when you hear these noises, drive your vehicle to the mechanic immediately.

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