The transmission undergoes a lot of stress. The grit you see in used transmission fluid is actually bits of metal that wear off the gears in the transmission. In addition to that, the transmission operates at very high temperatures. Usually it’s 100 to 150 degrees higher than engine temperatures. Those high temperatures eventually cause the transmission fluid to start to break down and loose efficiency.
As the fluid gets older, it gets gritty and doesn’t lubricate and cool the transmission as well – leading to even more wear. The fluid can actually get sludgy and plug up the maze of fluid passages inside the transmission. At best, your transmission won’t operate smoothly. At worse, it could lead to costly damage.
When your transmission is running properly, it transfers more power from your engine to the drive wheels, and improves fuel economy. That’s why manufacturers recommend changing your transmission fluid at regular intervals. Your owner’s manual has a schedule for transmission service and, of course, your service center can tell you what the manufacturer recommends.
Hot and dusty conditions; towing, hauling, stop and go conditions and jack rabbit starts all increase the load on the transmission and its internal temperature. That means you need to change the fluid more often. A good rule of thumb is every 35,000 miles, 55,000 kilometers or two years. If your manufacturer suggests more frequent intervals or if you’re driving under severe service conditions, you will need to change it more often.
Most service centers have the ability to perform a transmission service while you wait and the cost is quite reasonable. It’s downright cheap when you think about how much a major transmission repair can cost! Your service technician will know the right type of transmission fluid to use. If it’s getting to be time to have your transmission serviced, do your car a favor and have it done. If not this time, then on your next service stop.