Transmission fluid can be surprisingly colorful, especially if you've never seen it before and don't know what to expect. The color of your transmission fluid is one of the best early warning signs of transmission problems, so it is important to check your own fluid or have it checked as part of your regular vehicle maintenance program. Your transmission fluid should be changed every two to three years, or 24,000 to 36,000 miles.
If the transmission fluid in your car is pink, red or even very light reddish-brown, the transmission fluid is just fine. These are the colors your transmission fluid is supposed to be. There are a variety of different brands of transmission fluid, which accounts for the variation in shade, but overall your transmission fluid should have a reddish tint to it. Brand new fluid will be lighter in color than fluid that has been in your car for a year or two.
Dark brown or black transmission fluid is a sign of old or burnt transmission fluid. If your fluid is dark brown or black, it needs to be changed, and your transmission should be checked for problems to make sure it is not overheating and burning the fluid.
Your transmission fluid should be translucent. Dark, cloudy, creamy, milky or opaque transmission fluid is a sign of a problem with the transmission. Sometimes this is caused by coolant being forced into the transmission by a faulty radiator. It can also be caused by water or debris in the transmission. If your transmission fluid is not clear/translucent, you need to take your car to a transmission specialist and determine why. At the very least, your transmission fluid will need to be changed.
