Torque Shop: Noisy wheel bearings
Sign up now: Get ST's newsletters delivered to your inbox
Rhythmic humming: The bearing connects the wheels to the car's axle and can become noisy when it is worn.
PHOTO: PEXELS
Follow topic:
I started hearing a rhythmic humming sound seemingly coming from the back of the car when I drove above 60kmh. The sound became less obvious after I changed the tyres some months ago, but it became louder again recently.
It is not easy to pinpoint the fault based on your brief description, but here are some areas that may be causing the noise.
Since you have replaced the tyres, and it is assumed they are new and of good quality, the noise is more likely to come from the wheel bearings. They are, after all, wear-and-tear components and a very common source of the type of noise you experience.
The bearings connect the wheels to the axle. Although bearings should last well beyond 100,000km, premature wear can happen, usually due to manufacturing defects.
If left unattended, the noise will only get louder and, eventually, the bearing can fail. This can lead to a loss of control of the vehicle and braking problems, and the wheel can even come off.
Hence, if it is diagnosed as a bearing problem, replace both your rear-wheel bearings as soon as possible.
Wheel bearings vary widely in price, depending on the make and model of the car. If there are no symptoms, it is not mandatory to replace the wheel bearings at the front axle at the same time.
The only other item left to check is your exhaust pipe.
A leak in your exhaust pipe, or if the pipe is hanging and touching some part of the chassis due to a failed hangar, will create some humming and rhythmic noises. If the exhaust pipe is not isolated from the chassis with rubber hangars, vibrations from the engine can be transmitted and sometimes amplified through the exhaust pipe into the body.
