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Noise While Driving

Monitor

A hum, whir, or drone that changes with vehicle speed usually comes from a rotating component. Wheel bearings are the most common cause of a speed-proportional hum that changes when you shift your weight slightly side to side while driving. Cupped tires produce a similar droning sound. Belt-driven accessories — alternator, AC compressor, power steering pump, water pump — produce a higher-frequency whine or squeal that does not always change cleanly with road speed.

Monitor closely — watch for other symptoms developing.

Check These First

Before diving into diagnosis, quickly verify these:

  • 1Note whether the noise changes directly with speed — louder as you go faster and quieter as you slow down.
  • 2At highway speed, try gently weaving side to side in your lane. If the noise changes when you load one side, a wheel bearing is likely.
  • 3Coast at highway speed and shift from Drive to Neutral — if the noise stays the same, the drivetrain is not the source.
  • 4Listen for changes when turning sharply in a parking lot at low speed — a humming bearing often changes during slow turns.
  • 5Check whether the noise is present at all speeds or only within a specific speed range, which can help identify the source.

What exactly is it doing?

Pick the description that fits best.