“What’s That Strange Hum?” Three Common Causes of Wheel Noise That Aren’t Suspension Problems

Most motorists understand that a properly functioning vehicle shouldn’t produce any strange sounds beyond the normal noise that comes from its components doing their job. When an odd hum or rumble seems to be coming from the wheels, the first instinct is usually to suspect a suspension issue. But that’s not always the case. In fact, there are several other common reasons a vehicle might make noises that appear to come from the wheels.

If you rule out suspension problems right away, mechanics say there are typically three other causes behind these mysterious sounds. In fact, technicians at repair shops say these issues account for roughly nine out of ten cases where drivers complain about unexplained wheel noise. Before heading to a professional mechanic, it may be worth checking a few things yourself.

One possible culprit is the controlled suspension system, a component designed to dampen pressure pulsations from the pump. Drivers often notice a low humming sound while the car is moving. In many cases, the source of the noise is the hydraulic lines connected to the vehicle’s adaptive suspension system. Even after repairs are completed, the noise may linger for a short time before gradually disappearing.

Another common cause is the bearings in engine-driven accessories. After inspecting the suspension, these components should usually be checked next. Problems often occur in the alternator or the water pump in the cooling system. Because these parts are typically mounted low on the engine, the noise they produce can easily be mistaken for something coming from the wheels.

Finally, don’t overlook the transmission mount. If the mount supporting the automatic transmission has worn out, it can also generate unusual noises. In many cases, the problem is made worse by loosened mounting hardware, which allows additional vibration and sound to travel through the vehicle’s structure.