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While you may depend on a transmission repair shop in Charlotte, NC for your transmission problems and maintenance, being knowledgeable about some of the things that may be needed to keep your transmission operational can help you save time and money, and help you know if your transmission shop is trustworthy. One thing shops often offer or suggest is a transmission flush, so below is some information about what a transmission flush is and when it is needed.

What is it?

A transmission flush is when a transmission repair shop drains all of the transmission fluid out of your transmission and puts new fluid in. Often, a special machine is used to pump a cleaning solution through the lines before they are refilled with the fresh transmission fluid. This removes debris and sludge, and replaces the old transmission fluid, which can become contaminated with tiny metal filaments over time, with new fluid without any of the old left over to damage the fresh oil. It is suggested for a transmission flush to be done every 24,000-30,000 miles, depending on your car and how you drive. Talk to your transmission tech to get a good estimate of when you should consider scheduling a transmission flush.

Does it work?

Most transmission repair shops agree that a transmission flush is a good maintenance procedure to have done occasionally. It can remove residue and materials from the transmission lines and increase the life of your transmission. Some people believe that if the machines used to conduct the flush are calibrated incorrectly, they can use too much pressure during the flush and damage the lines and seals in the transmission, which can of course cause further damage down the road. If you are concerned, talk to your transmission repair shop about how they calibrate their machines and if their transmission flushes ever lead to complications.

How is it different from a change?

The goal of both a transmission fluid change and a transmission flush are the same — to replace the old transmission fluid with the new, thereby increasing the performance and life of your vehicle — but how they go about it and the effectiveness of them are very different. A transmission fluid change relies on gravity to pull as much transmission fluid as possible out of your transmission. Because oil is a thicker liquid (potentially made thicker still by contaminants), it drains slowly and may leave contaminants and sludge behind. Experts say most transmission fluid drains only remove 20-40% of the transmission fluid in the system, leaving the rest behind to contaminate the new fluid. A flush uses pressure to push out all the old fluid, then runs a cleaning solution through, ensuring that the new transmission fluid going in will not be contaminated by what was in there before. Ideally, after a change or a flush, the pan will be dropped so that the transmission repair tech can make sure there is no debris in the pan or filter. The filter may need changing if it has caught too much debris before and during the change or flush.