Whether you drive stick shift or prefer automatic, you should know how to spot signs of transmission problems. Catching a problem early can help prevent further damage to your vehicle.
It's important to keep an eye on transmission fluid levels and to watch for leaks. For vehicles equipped with automatic transmissions, there is usually a dipstick that allows you to easily check the levels. Manual transmissions are less likely to have this convenience, and you will need to inspect the liquid at the source, usually through the same spot where you add more fluid.
The quality of transmission fluid is essential to the system's health. In the case of automatic trannies, the liquid should be bright red or reddish-orange, clear and free of debris. If you sniff it, the smell should be mildly sweet - just be careful not to breathe the chemicals in too deeply. An odor that has a burnt quality, a dark brown or black hue and low levels are all signs that the fluid needs to be changed.
In order to determine if there is a leak, you can place a light sheet of paper underneath your vehicle overnight, or park it on light pavement if you have the option. In the morning, look for spots of red liquid, or reddish stains on the paper or ground, which likely indicate a leak. This should be addressed as soon as possible to preserve your vehicle's transmission health.
Another signal that the transmission needs attention is the check engine light, which can also be activated by a number of other issues. Sounds and sensations can also be clear indicators of transmission problems. The gears may grind when you try to shift a manual transmission, which may mean the clutch is worn or needs to be adjusted. This could also indicate that the gear synchronizers or shift linkage need to be inspected for wear or damage.
Drivers with automatic transmission problems may actually notice when their vehicles shift gears, whereas healthy systems would make the transition without much commotion. The engine may also lurch from one gear to the next.
You should also pay attention to the sounds your car is making if you suspect there is a transmission problem. Often times, for both manual and automatic, a problem can be accompanied by a whining, buzzing or clunking sound when the gears shift. These sounds will be much more prominent in cars with stick shifts, and it is important to note that similar noises can also point to other issues.