Is That Noise Your Transmission Or Something Else?

Posted on: 23 November 2021

Many modern vehicles now use all-wheel drive (AWD) or four-wheel drive (4WD) systems. These systems rely on a few extra components when compared to traditional two-wheel drive (2WD) vehicles. Instead of driving only a single axle, AWD and 4WD systems must send power to all four wheels, although they do so in a few different ways.

The added complexity in these systems can make it somewhat more challenging to narrow down possible problems. Symptoms that might point to the transmission in a 2WD vehicle may instead be an issue with the differential or transfer case in AWD and 4WD cars. Recognizing what different sounds mean can help you differentiate between these problems.

Why Do Transmissions Make Noise?

A modern automatic transmission in good repair should generally be smooth and silent while in operation. You shouldn't notice any noises or vibrations in any gear. This situation can change as interior parts wear and fail, or due to fluid issues such as contaminated fluid or low pressure. Some typical problem noises include whining, grinding, or buzzing sounds.

It's often challenging to diagnose the underlying cause of a transmission noise simply by comparing noises against each other, but you can get some clues based on when the noises occur. For example, fluid issues usually cause noises at any speed, and you may not notice much change while accelerating or changing gears.

On the other hand, failures due to internal wear usually show up only when the vehicle is in a certain gear. You may hear a noise as your car shifts into second or fourth gear, but nothing in other gears. These sounds often occur when internal parts become scored or pitted. These gear-related sounds typically won't change much based on speed.

How Do You Know It's a Transmission Noise?

Unfortunately, the whining or buzzing you'll hear from a transmission in trouble is often similar to the sounds you'll hear from a failing differential or transfer case. These components also tend to produce whining, buzzing, and grinding noises. The best way to tell the difference is by listening for issues when you hear the sounds.

In general, constant noises that change with speed often point to a problem with one of these other components. If your transmission allows you to select gears manually, you can try changing gears and listening for any noise changes. If the sound goes away as you choose gears or doesn't change with engine speed, you're more likely facing a transmission problem.

Remember that automatic transmissions are incredibly complex. While you can use your ears to perform some basic detective work, you should always rely on a skilled transmission shop to perform a final diagnosis and repair. Since waiting to address transmission issues can potentially lead to costly builds, it's usually a good idea to have your car evaluated as soon as you hear an unusual noise.

For more information, contact a transmission repair service near you.