Loading

Are transmission flushes really necessary?

The short answer is that transmission flushes are generally not necessary for most vehicles, unless specifically recommended by the manufacturer. Transmission fluid is designed to last the lifetime of the vehicle, and regular fluid changes are usually sufficient to maintain the health of the transmission.


Understanding Transmission Flushes


A transmission flush is a service where the old transmission fluid is completely drained and replaced with new fluid. This is different from a simple fluid change, where only a portion of the old fluid is removed and replaced. Proponents of transmission flushes argue that they help remove built-up deposits and contaminants, improving the transmission's performance and longevity.


When Are Transmission Flushes Recommended?



  • Manufacturer Recommendation: Some vehicle manufacturers may recommend a transmission flush at specific mileage intervals, usually around 60,000-100,000 miles. Following the manufacturer's guidance is important to maintain the warranty.

  • Transmission Issues: If the transmission is exhibiting problems, such as slipping, hard shifting, or unusual noises, a flush may help address the issue by removing built-up debris.

  • Fluid Condition: If the transmission fluid appears discolored, smells burnt, or has a gritty texture, a flush may be warranted to remove the contaminated fluid.


In most cases, regular fluid changes every 30,000-60,000 miles are sufficient to maintain the transmission's health, and a flush is not necessary.


Potential Risks of Transmission Flushes


While transmission flushes can be beneficial in some cases, they also carry some risks that should be considered:



  • Dislodging Debris: The high-pressure flushing can dislodge built-up debris in the transmission, which can then circulate and potentially clog narrow passages or damage components.

  • Fluid Compatibility: If the new fluid is not compatible with the existing fluid, it can cause issues or even damage the transmission.

  • Existing Transmission Problems: If the transmission is already in poor condition, a flush may not fix the underlying problem and could potentially make it worse.


For these reasons, it's important to consult with a qualified mechanic before deciding to have a transmission flush performed on your vehicle.

Which is better, a transmission flush or drain?


With a flush, all the old fluid is removed by a flush machine and replaced with new fluid, allowing for optimal transmission performance. A fluid change is a drain-and-refill, with some old fluid remains in the transmission after the change, which can contaminate the new fluid — and diminish performance.



How much does a full transmission flush cost?


Drivers can expect to pay $125 to $250 for a transmission fluid flush service. This is approximately twice as much as a transmission fluid change. This is due in large part to the additional fluid required. A flush will take 12 to 22 quarts, while a fluid change requires 5 to 7 quarts.



What happens if you don't get a transmission flush?


Costly Repairs: Ignoring transmission fluid changes can result in significant damage that may require expensive repairs or even a complete transmission replacement. Decreased Performance: You may notice a decline in your vehicle's overall performance, including reduced fuel efficiency and responsiveness.



Do mechanics recommend a transmission flush?


Many auto manufacturers suggest having an automatic transmission flushed once every 30,000 to 100,000 miles. For a manual transmission, it usually ranges from 30,000 to 60,000 miles. It's worth noting that some manufacturers don't recommend a flush at all, at least for certain models.



Should I flush my transmission after 100k miles?


In the past, the factory-recommended interval for changing the automatic transmission fluid was typically between 30,000 and 100,000 miles, but some newer vehicles have what's referred to as “lifetime fluid.” However, there's some question as to whether never changing the transmission fluid may shorten that “lifetime.” ...



How much should a transmission flush cost?


Drivers can expect to pay $125 to $250 for a transmission fluid flush service. This is approximately twice as much as a transmission fluid change. This is due in large part to the additional fluid required. A flush will take 12 to 22 quarts, while a fluid change requires 5 to 7 quarts.



What mileage is good for a transmission flush?


Automatic: Every 60,000 to 100,000 miles
It's important to change your transmission fluid, but the type of transmission you have affects your ideal changing interval. If you drive manual, most manufacturers will recommend changing your transmission fluid every 30,000 to 60,000 miles.



Why do mechanics say not to change transmission fluid?


That bad fluid may have a “sticky” quality to it or metal flecks that act to aid friction, and if it's changed, the new fluid might cause the transmission to start slipping.



Do you really need to flush transmission fluid?


Much like oil changes, transmission flushes should be performed every so often to maintain the transmission system, which you cannot drive without. If you bring your car in so our technicians can complete this service, your vehicle can stay running at its best.



What is the downside of transmission flush?


This is because excess build-up from contaminants and debris solidify and form a sludge. If too much sludge builds up in your transmission, and a transmission flush is performed, new fluid can cause stubborn sludge to loosen and cause damage to your transmission.


Kevin's Auto

Kevin Bennett

Company Owner

Kevin Bennet is the founder and owner of Kevin's Autos, a leading automotive service provider in Australia. With a deep commitment to customer satisfaction and years of industry expertise, Kevin uses his blog to answer the most common questions posed by his customers. From maintenance tips to troubleshooting advice, Kevin's articles are designed to empower drivers with the knowledge they need to keep their vehicles running smoothly and safely.