You just took your car in for its regular transmission service. You have the transmission serviced about every two years, because you’d like to avoid having to spend money on a rebuild. The service writer asks, “Would you like a complete fluid exchange service at the same time?” You smile. You know that’s a scam. If it weren’t, it’d be recommended in your owners manual. They’re just looking for a way to charge you more money, right?
Not even close. A transmission fluid exchange is more than just a real service: It’s a worthwhile addition to your regular maintenance routine. Here’s why: During the more familiar transmission service, the technician removes the pan and replaces the filter. Then he reinstalls the pan and refills the transmission.
That type of service is valuable and worthwhile, but it only replaces part of the transmission fluid. In some cases, less than half of the fluid is replaced. The rest of the old, worn out fluid remains in the transmission. That’s important, because transmission fluid does more than just lubricate the transmission parts. It also cools the transmission, and even provides the connection between the engine and the wheels.
When automatic transmission fluid is squeezed between the clutch plates in the transmission, the fluid takes on a new characteristic. It acts like little “Velcro” hooks, to help the clutches grab onto one another. That holding characteristic is critical for the transmission to operate properly.
Over time, the little “hooks” in the oil wear out, through a process known as shear. When shear occurs, the transmission will begin to slip and generate huge amounts of heat. It won’t be long before the transmission is damaged from excessive temperatures.
When you have the transmission serviced normally, it replaces only a part of the worn-out fluid. The rest is left in, which can allow the transmission to slip and wear. A fluid exchange service replaces nearly all of the fluid in the transmission, which helps the transmission clutches hold tigher. This reduces heat, and can keep the transmission working for years to come.
The best type of transmission service includes both the basic filter replacement and a fluid exchange service. The filter replacement service allows the technician to examine the material in the sump, to identify potential problems and make educated recommendations for your transmission. Then the fluid exchange replaces the worn fluid, so your transmission can have a reasonable chance to last for many years.
In fact, most technicians will readily admit that if you have your cars automatic transmission serviced every two years or so, you’ll probably never need the transmission rebuilt, as long as you own your car. That’s a worthwhile service investment by any standards!
Most ATRA Members can offer you both the basic transmission service and the fluid exchange service. And they have highly trained technicians available who can evaluate your transmission through a simple road test and by examining the sediment in the bottom of the pan.
To find the ATRA Member shop near you, click the Shopfinder link.
If you have any questions you can e-mail them to ATRA's Technical Department through the Technical Services page or call 1-866-GO-4-ATRA (1-866-464-2872)