How It Works 

As cars continue to evolve, so do their transmissions. One of the more recent innovations in transmissions is the Continuously Variable Transmission, or CVT. A CVT is a type of automatic transmission that doesn't have traditional gears, instead it has a belt and pulley system that allows for an infinite number of gear ratios. Unlike traditional automatic transmissions, which use a set number of gears, a CVT uses a system of pulleys and belts or chains to vary the gear ratio continuously.

The CVT system consists of two pulleys connected by a belt or chain. Each pulley has two halves that can move closer together or farther apart, depending on the desired gear ratio. The pulleys are controlled by a hydraulic or electronic system that adjusts the position of the pulley halves based on the driver's input and the vehicle's operating conditions.

When the driver presses the accelerator pedal, the system senses the demand for acceleration and adjusts the pulley positions to provide the optimal gear ratio for the speed and load conditions. This allows the engine to operate at its most efficient speed and provides a smooth and responsive driving experience.

The CVT system is particularly useful for vehicles that require smooth and efficient acceleration, such as hybrid and electric cars, and it can also improve fuel efficiency by keeping the engine operating in its optimal range. 

While CVTs have been praised for their smooth operation and improved fuel efficiency, they are not without their issues.

Why They Fail

Some of the most common problems with CVTs include belt slipping, overheating, and electrical issues. In addition, certain automakers have had historic issues with CVT failures. For example, Nissan has faced class action lawsuits related to CVT failures in their vehicles. Other automakers, such as Jeep, Mitsubishi, Subaru, and Honda, have also had some issues with their CVT transmissions.

That being said, the current crop of CVT transmissions are more reliable than the first generation units. Over the years, automakers have made improvements to the design and manufacturing of CVT transmissions, which has helped to address some of the issues that were seen in early models. For example, improvements have been made to the materials used for the belts and pulleys, which has helped to reduce the risk of slipping and other types of damage. In addition, better cooling systems have been developed, which helps to prevent overheating.

Despite these improvements, it's still possible for CVT transmissions to experience problems. As with any mechanical component, wear and tear can eventually lead to issues, and problems can arise if the transmission is not properly maintained or if the vehicle is operated in a way that puts undue stress on the transmission.

Overall, CVT transmissions have become more reliable over time, and many car owners have reported long periods of trouble-free use. The list below looks at reasons of failure across the generations, and is not specific to any vehicle brand or year.

CVT gearboxes have been known to fail due to a variety of reasons, including:

Overheating: CVT gearboxes are prone to overheating, which can cause damage to the transmission. This can occur when the transmission is worked hard, such as when driving up steep hills or towing heavy loads.

Lack of maintenance: Like any other component in a vehicle, CVT gearboxes require regular maintenance. If the transmission fluid is not changed regularly or the transmission is not properly serviced, it can lead to premature failure.

Electronic problems: CVT gearboxes rely on electronic sensors and control modules to function properly. If these components fail, it can lead to transmission problems.

Poor driving habits: Driving habits, such as frequently driving at high speeds or sudden acceleration and deceleration, can put extra stress on the transmission and lead to premature failure.

It's important to note that not all CVT gearboxes are prone to failure and that proper maintenance and driving habits can help extend the life of the transmission. Additionally, some automakers have improved the design and reliability of their CVT gearboxes in recent years.

To Repair Or Replace?

CVT gearboxes can sometimes be repaired, but in many cases, replacement is the only option. The cost of repairing or replacing a CVT gearbox can vary widely depending on several factors, such as the make and model of the vehicle, the severity of the damage, and the location where the work is done.

In general, CVT gearbox replacement can be a very expensive repair. In broad terms, the cost of a new CVT gearbox can range from R60 000 to  R150 000 or more, depending on the vehicle and the manufacturer. Labour costs can also add to the overall expense, with CVT gearbox replacement often taking several hours of work.

Repair costs for a CVT gearbox can also vary depending on the extent of the damage. Minor repairs, such as replacing a damaged belt or pulley, may cost a few thousand rands, while more significant repairs, such as replacing the entire transmission or rebuilding it, can cost tens of thousands of Rands.

It's important to note that repair or replacement costs can also vary depending on the availability of replacement parts and the expertise of the mechanic performing the work. It's important to choose a qualified mechanic with experience working on CVT gearboxes to ensure that the repair is done correctly and to prevent further damage.

Repairing or replacing a CVT is not always a viable option. Whether or not it's worth selling or scrapping a vehicle when the CVT goes depends on several factors, including the overall condition of the vehicle, the cost of repairing or replacing the CVT, and the value of the vehicle.

I always take the cynical view when I see used CVT vehicles for sale, with relatively high mileage and at a good price, that there will be undisclosed problems with the CVT. There is a previous blog I have written on the StartMyCar website which deals with how to test drive a CVT vehicle to feel if there are problems with the CVT. Early-stage CVT problems won’t necessarily rear their head on a small sedate test drive around the block.

Not all CVT failures are sudden, which is why many unscrupulous owners trade-in their vehicles at the first whiff of trouble. CVT transmissions can fail in different ways, and the symptoms can vary depending on the type and severity of the problem. In some cases, CVT failures may be sudden, with the transmission failing completely and the vehicle becoming undriveable. This type of failure can be caused by a variety of issues, such as a broken belt or pulley, a malfunctioning valve body, or a problem with the electronic control module.

In other cases, and these are the ones you need to be more wary of, CVT failures may be more gradual, with the transmission exhibiting symptoms such as slipping, shuddering, or a loss of power over time.

Tips To Prevent Premature CVT Failure

To prevent premature failure of a CVT gearbox, there are several steps that you can take:

Follow the manufacturer's recommended maintenance schedule: Regular maintenance, including changing the transmission fluid and filter, is crucial to the longevity of the CVT gearbox. Make sure to follow the manufacturer's recommended maintenance schedule to keep the transmission in good condition.

Use the correct transmission fluid: Using the wrong type of transmission fluid can cause damage to the CVT gearbox. Make sure to use the type of fluid recommended by the manufacturer.

Avoid harsh driving habits: Harsh driving habits, such as rapid acceleration and hard braking, can put extra stress on the CVT gearbox and cause premature failure. Try to drive smoothly and avoid sudden changes in speed.

Avoid overloading the vehicle: Overloading the vehicle with too much weight can put extra stress on the CVT gearbox, causing it to wear out more quickly. Make sure to stay within the vehicle's weight limits.

Keep the transmission cool: Overheating is a common cause of premature failure in CVT gearboxes. Avoid driving the vehicle in extreme heat, and make sure that the transmission is properly cooled.

Monitor for signs of problems: Keep an eye out for signs of problems with the CVT gearbox, such as slipping, shuddering, or strange noises. If you notice any issues, have the transmission inspected by a qualified mechanic as soon as possible.

By following these tips, you can help prevent premature failure of the CVT gearbox and extend its lifespan. It's important to address any symptoms of a failing CVT as soon as possible, as continuing to drive with a faulty transmission can lead to further damage and potentially more costly repairs. Regular maintenance and prompt attention to any warning signs can help to minimize the risk of a sudden or catastrophic failure.

How We Can Help

As an auto spares store, we understand how frustrating it can be to deal with a failing CVT transmission. Unfortunately, when it comes to CVT transmissions, there are not many options for repair or replacement parts. We do not sell CVT replacement parts, nor do we recommend any particular places or mechanics that specialize in CVT repairs or replacements.

However, we do offer over 30,000 other parts to help keep your vehicle running smoothly. Our extensive range includes parts for engines, brakes, suspension, steering, electrical systems, and much more. We are committed to providing our customers with high-quality parts at competitive prices, and we pride ourselves on our excellent customer service and technical expertise.

If you're experiencing problems with your CVT transmission, we recommend consulting with a qualified mechanic or dealership to explore your options for repair or replacement. In the meantime, we invite you to visit our website, www.Startmycar.co.za,  and browse our extensive range of parts to find everything you need to keep your vehicle running smoothly.