My car sounds like an airplane. Why?

In this series of Q&A posts, we are using google’s autocomplete function to find the most commonly asked questions about cars and giving them each a definitive answer. This series is ongoing and you can find more of our Q&A articles right here.

Why does my car sound like an airplane?

You would be shocked at how often we hear this one!  Sometimes it can be tricky to diagnose, only because what some people call an “airplane” noise someone else might call a “growl,” “hum,” or “sputtering”. If they are describing the sound of a sputtering World War I biplane I would be inclined to think it is an exhaust leak issue. More often then not the sound they are describing is more like the former, a steady growling or hum that increases in pitch and gets louder as the vehicle accelerates. Usually this is caused by a wheel bearing.
 

What’s a wheel bearing? It’s a set of steel balls, held together by a metal ring called a race. There are many different styles of bearings but they are all very similar and all do the same job: they help something spin with very little friction.

 
Most wheel bearings manufactured today are sealed bearings. They come from the factory pressed together as an assembly. Seals protect bearings from the elements, water, and debris, and they also seal in high-temperature grease the bearing needs to operate. When the seal is broken or damaged, the wheel bearing will fail and start making noise. Many describe this as an airplane noise, but others might say it is like driving over a rumble strip on the side of the highway or the whirring of a helicopter propeller.

Bottom Line: No matter how you describe it, wheel bearing issues need to be sorted out asap, especially considering the noise will get louder and louder the longer you leave it. We are a phone call away if you need us to look into something, we are happy to help.