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What is a Transmission Flush? Signs, Facts & FAQs

automatic transmission repair

Taking your vehicle for a routine checkup or frequent servicing can help your car work properly for a much longer time. One such aspect of servicing your car from time to time is a transmission flush. A transmission flush consists of draining and removing the automatic transmission fluid from a car’s transmission and replacing it with fresh fluid. This procedure is vital to keep your transmission clean and durable.

If you are interested in how this process works and whether it is a requirement, read the article below, as we will supply you with all the information necessary.

car and road divider

What is a Transmission Flush?

A transmission flush is an essential procedure that prolongs the lifespan of your vehicle and the general performance of the automatic transmission on your car. This procedure removes oil with the particles and debris accumulated in your transmission over time and replaces it with new and fresh oil. The purpose of the automatic transmission fluid is to cool your automatic transmission and provide better general performance while reducing harmful friction.

Since transmission fluid collects debris over time, it can cause the transmission to produce more heat and friction. This can significantly affect the performance of the transmission and acceleration.

mechanic checking automatic transmis
Image By: Setta Sornnoi, Shutterstock

The Importance of a Transmission Flush

An automatic transmission is one of the most expensive parts in a vehicle to replace, so it is crucial to maintain it properly to prolong its lifespan. A transmission flush on a car is necessary to have a polished and healthy vehicle for a long time. It is an effective preventive maintenance procedure. Since transmission fluid is required to maintain the optimal temperature in a car, if it is not frequently changed, it can lead to severe problems and even transmission deterioration.

Does Your Car Need a Transmission Flush?

A transmission flush is a very effective and crucial preventive maintenance procedure, as it can help you save a lot of time and effort down the road for any expensive transmission repairs. A transmission flush is most definitely necessary for all automatic vehicles; the only uncertainty is how often you should do it on your car. Regularly taking your car for servicing and preventive maintenance can be the best decision you can make and can save you a lot of time and money in the long run.

car and road divider

Signs Your Car Needs a Transmission Flush

You will hear or find many signs on your car that will indicate that your car needs a transmission flush. It is best to look out for these signs to act in time and prevent any severe failures and damages to your transmission. When you notice these signs, it is crucial to take your car to the repair shop as soon as possible.

  • Shifting Gears: The first and most obvious symptom you may notice can be the poor coordination of shifting gears. You will notice this problem very early on, as you will feel it during driving, and it may cause your transmission to shift gears entirely out of sync, too fast, or too late.
  • Grinding Noises: As soon as you notice a strange sound coming from your transmission while driving, you may need to check the transmission fluid level in your transmission. If the fluid level is sufficient, your transmission most likely needs a flush.
  • Coloring: Another way to check if the fluid in your transmission is still okay to work with and run your car properly is to check its color. Fresh transmission fluid is colored bright red,  so if the fluid in your car is dark red or even brown, debris and other foreign particles have accumulated in your transmission, and it needs a flush.
man driving automatic transmission car
Image Credit: Alexander Tolstykh, Shutterstock

How Often Do You Need to Flush Your Transmission?

The frequency of a transmission flush will depend on many factors. You may need to consider the model of a car you own, the manufacturer, and the miles you’ve traveled. It is best to contact your manufacturer to know how many miles your car can travel without a transmission flush.

Most manufacturers’ typical interval for a transmission flush is every 3 to 5 years or 30,000–50,000 miles. Some manufacturers will advise you to have a transmission flush after only 100,000 miles. This is why it is essential to read your vehicle owner’s manual, as it will contain all information necessary for that particular vehicle’s transmission.

car and road divider

Final Thoughts

This article contains many details about a transmission flush, what it is, why it is so important, and how to know when you need a transmission flush. Read this article carefully and save yourself a lot of time, effort, and money on unnecessary, expensive transmission repairs. Being well informed on this topic can help you immensely when you find yourself in a situation needing to determine the problem in your car on your own.

Featured Image Credit: Setta Sornnoi, Shutterstock


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