Modern automatic Transmissions are extremely complex and require the use of specialized fluids. The transmission will not shift or perform the way it is designed if it has the wrong fluid in it, or the fluid is not at the correct level. We always use the specified fluid or higher quality performance synthetic that meets or exceeds the manufacturer’s fluid specifications. Similar to oil changes, the transmission should also have periodic service. Typically the first transmission service is due around 60,000 miles (sometimes sooner depending upon the condition of the fluid). From that point and on, we recommend changing the fluid every 30,000 miles after that. For those who are towing we would recommend having the transmission service every 25,000 mile intervals. We tend to not rely on the manufacturer’s suggested mileage service intervals (at least here in Santa Cruz) since most of the driving locally requires much more shifting of the transmission, which is what breaks down the fluid.
