5 Signs that Your Transmission Fluid Needs Replacing

5 Signs that Your Transmission Fluid Needs Replacing

23rd Jun 2016

When was the last time that you changed your vehicle's transmission fluid? While most drivers recognize the importance of changing engine oil, many overlook the transmission fluid. As a result, debris accumulates within the transmission, shortening its lifespan while increasing the risk of failure. But how exactly do you know when it's time to change your vehicle's transmission oil?

Black, Dark Color

One tall-tale sign that transmission fluid needs to be changed is the color. Transmission fluid typically has a pink-red color, but as it ages, it begins to darken before eventually turning black. So, pop your vehicle's hood and pull the dipstick from the transmission, inspecting its color. If your transmission color is black or dark brown, it's probably a good idea to replace it.

Difficulty Shifting Gear

If your car fails to shift gears properly -- whether it's an automatic or manual transmission -- it could be a sign of bad transmission fluid, in which case you should change it ASAP. Clean transmission fluid flows more freely through the transmission. When debris accumulates inside it, however, the fluid turns into a sludge-like consistency, making it difficult to reach all of the internal components of the transmission. And when this happens, it may cause resistance or other problems when attempting to shift gears.


When transmission fluid becomes dirty, it may cause surging when either the gas or brake pedal is pressed. This is because the contaminants in the fluid create an inconsistent flow into the transmission So your transmission may receive lots of fluid at one point, and then little fluid the next.

Strange Noises

Of course, another tall-tale sign that your transmission fluid needs changing is strange noises. Grinding is one such noise that's a clear indication of low and/or dirty transmission fluid. If you hear a grinding noise, check your transmission fluid to ensure it has proper color and is not low.

Automaker's Recommendations

There's no better way to tell when a vehicle's transmission fluid needs to be changed than by looking in the owner's manual. Here, you'll find the automaker's recommendations for service maintenance, including transmission oil changes. Depending on the make and model vehicle, automaker's may recommend changing the transmission oil as frequently as once every 15,000 miles, or for longer intervals, such as once every 50,000 miles.