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Does My Transmission Fluid Need to Be Flushed?

does my transmission need to be flushedWhile your engine is working to power your vehicle, your transmission is working hard to send the power to the wheels based on your desired speed. Because of its vital role, you want to ensure your transmission stays in peak condition to send power to your wheels for years to come. Otherwise, you might end up using your feet to spin your wheels like Fred Flinstone. So how can you help extend the life of your transmission? Preventative maintenance is a good start! Similar to your engine, your transmission needs fluid to cool and lubricate for efficient operation. But what if you have a “sealed transmission?” Does your car still need a transmission flush? Find out if you should flush your transmission and if so, how often.

As you drive, your transmission heats up from the friction created to power the wheels. Over time, the heat causes metal shavings to flake off and mix with dirt and other contaminants in the transmission fluid. After a while, the fluid becomes discolored from heat and loses its ability to protect the transmission as well as it once did. To ensure the transmission continues functioning optimally, automakers recommended flushing the fluid every 30,000 to 60,000 miles. Here are three reasons why you should have your transmission fluid flushed:


  • Improve fuel efficiency


When the transmission is in peak condition and functioning well, there is less stress on mechanical components in the vehicle. With a reduction in friction often produced by rotating and constantly moving parts, the energy dramatically increases and is directed to the wheels, which greatly improves fuel economy.


  • Prevent overheating


After a certain period of driving, flecks from the transmission and metal shavings build up in the transmission fluid. As the transmission moves it produces heat that also heats the transmission fluid causing it to burn and overheat the internal components which can lead to system failures.


  • Improve gear operation


Overheated transmissions have a negative effect on transmission fluid, it loses its ability to lubricate properly. When services are neglected the fluid turns it into a thick, gooey sludge that obstructs gears, making shifting gears between speeds a difficult task. 

When to Flush Transmission Fluid

A transmission flush removes all spent, dirty fluid from the transmission, and it is replaced with fresh, clean fluid. Fresh fluid makes the transmission run cooler, provides more consistent and smoother shifting while providing protection against wear on clutches, gears, and bearings. Another benefit of adding fresh transmission fluid is its cleansing ability. Sludge and other particulates that have accumulated in the fluid flow through the transmission and may become trapped in the filter. Just like an engine oil filter, the transmission filter traps the contaminants, if disregarded, there is a likelihood that these particulates can become lodged in the valve body’s narrow passageways that cause poor shifting conditions. By having a flush performed, an additive is introduced into the system to help clean the transmission to remove sludge and other impurities which could save you from the potential of costly repairs. This service should be performed every 3 years or every 45,000 miles. 

Sealed Transmissions and Fluid Flushes

It will be evident to you whether your vehicle has a sealed transmission or not just by locating the dipstick. Can’t find it? Your transmission is likely sealed. Even so, a sealed transmission should have its fluid checked and replaced at recommended service intervals. Though the name may be a bit misleading, the transmission still functions in the same way and thus, does require replenishment of the fluid. Not doing so can cause significant difficulties with the transmission that could lead to replacement or costly repairs. Though sealed, these transmissions are still accessible by a qualified technician.

Checking the transmission fluid on a sealed transmission is best left for the professionals. Even experienced DIYers should not attempt to do so. A minor mistake in the process could lead to major expenses for repairs or permanent damages. It is also possible that any tampering with the transmission, by unauthorized persons, could void any factory or extended warranties on the vehicle. An automotive professional has the ability to check the fluid using a special plug on the side of the transmission or by accessing it through the use of the car’s internal computer.

It’s best to stick to the timeline of having the fluid flushed every 30,000 to 50,000 miles as opposed to a last-ditch effort to save your transmission from failure. A fluid flush on an already failing transmission can prove detrimental. A transmission flush is meant to be a deterrent against damages, not a rescue measure. If you notice a grinding sound while driving or changing gears or a delay while shifting, take your vehicle to an automotive professional immediately. Continuing to drive with this trouble could only make things worse. 

Transmissions are vital to the movement of your vehicle. To keep your transmission in optimal condition, be sure to stick to a regular maintenance schedule. For all your transmission needs, whether for maintenance or repairs, seek out the transmission professionals at Sun Auto Service. You can trust that our technicians have the knowledge and expertise to perform maintenance and diagnose and repair transmissions properly. Plus, we guarantee all our work in writing with a 2-year/24,000-mile Nationwide warranty! For your next transmission inspection, service, or repair, give the Sun Auto Service team a call.