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The Sealed Transmission White Lie

Are you unsure as to whether or not your Corolla’s sealed CVT fluid should be replaced long before your car reaches 100,000 miles? This Toyota mechanic demonstrates what that fluid looks like when it has gotten too old; how often you really should consider exchanging your transmission fluid; and, how that this is a DIY maintenance task that will help your car last for many more miles.


White Lies, Myths, and Scams

This topic has been approached before; however, it is one that bears repeated reminding for car owners who are unsure what to believe when it comes to whether the fluid in a sealed transmission really does need to be changed…ever.

Related article: The Sealed Automatic Transmission Flush Deception Revealed by a Mechanic

Call it what you will---a white lie, a scam, or a myth---but the fact of the matter is that transmission fluid---just like your engine oil---does break down over time with use, over-heating, and exposure to moisture.

Earlier we had learned that the “missing transmission dipstick” is due to a change in the automotive industry to install sealed automatic transmissions into new cars.

The automotive makers extoll the virtues of a sealed automatic transmission in that it:

• Will no longer require the past 50,000-to-60,000-mile check and change requirement.

• Will provide customers with what they want by making vehicles almost entirely maintenance-free.

• Will save on significant oil production and disposal.

• Is totally unnecessary due to the advances made with synthetic oil.

Even today, we still hear service stories of service departments telling their customers that sealed transmissions do not require servicing because the transmission and fluid are engineered “to last the lifetime of the car” ---think about what this really means.

Related article: Transmission Problem Diagnosis with This Simple Tool

A 7-Year-Old Corolla After 106,000 Miles

To illustrate why transmission fluid replacement really should still be a maintenance service offered today, here is a recent Toyota Maintenance YouTube channel episode that demonstrates what the CVT fluid in a 2015 Toyota Corolla LE looks like compared to new fluid, after the car has gone through a little over 100,000 miles without servicing.

As an added bonus to the video, you will learn just how simple a transmission fluid maintenance task can be for the home mechanic as Peter shows you what tools and fluid you need to do the job.

Related article: Servicing Your Vehicle’s Automatic Transmission Can Be a DIY Project That Saves You Money

DIY Toyota CVT Continuously Variable Transmission

And finally…

Special note: Just a note in case you missed it as some comments from the video showed, Peter is only “exchanging” the fluid, meaning that he is diluting a fraction of the old fluid with new fluid---some of the old fluid remains in the transmission, even though it has been drained as demonstrated.

If you were to perform repeated “exchanges” the total fluid volume gets closer to being all new fluid. Peter is not replacing the filter in this demo. He is merely pointing out that he believes that doing this kind of exchange is a much better practice than simply never replacing the fluid till your car dies.

Related article: Easy and Correct Way to Change Your Transmission Fluid Without Removing the Pan

Related (related) article: Consumer Reports Car Experts Have This to Say About Whether You Should Pay More on Synthetic Oil for Your Oil Change

For more about maintenance that is essential need-to-know info, look at these three selected articles: “Used Car Transmission Problem Options You Need to Know” and “How to Inspect the Transmission Fluid on a Used Prius" and "Ford Escape Power Transfer Unit (PTU) Fluid Servicing is an Easy DIY Garage Project."

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Timothy Boyer is Torque News Tesla and EV reporter based in Cincinnati. Experienced with early car restorations, he regularly restores older vehicles with engine modifications for improved performance. Follow Tim on Twitter at @TimBoyerWrites for daily new and used vehicle news.

Image Source: Pixabay