Wheel Bearing Noise — How Shaw’s Diagnoses Which One and How Bad It Is

A failing wheel bearing typically produces a droning or humming noise that increases with road speed. The noise often varies when the vehicle is turned slightly — loading one side and unloading the other — and may reduce or disappear at certain speeds before returning. By the time it is loud enough to notice clearly, the bearing has usually been deteriorating for some time.

Which bearing is it

Diagnosing which corner of the vehicle has the failing bearing is the first challenge. The noise travels through the vehicle structure and can be misleading about its origin. Common methods:

• Weave test — at a safe speed on an empty road, the vehicle is gently weaved left and right. A wheel bearing that is failing will change in volume as the loading transfers between the two sides of the axle. If the noise increases when turning right, the failing bearing is typically on the left (the outside of the turn carries more load on a failing bearing). If it increases turning left, the right side is the likely source
• Jacking and spin test — with the vehicle safely on stands, each wheel is spun by hand and the bearing is felt for roughness, grittiness or play. A bearing that has deteriorated enough will show roughness that is detectable through the tyre
• Dial gauge play test — measuring lateral and axial play in the bearing with a dial gauge gives a quantitative measure of how worn the bearing is, which is particularly useful for borderline cases where the bearing is not yet dramatically noisy

What a borderline bearing means

A wheel bearing that is beginning to fail but has not yet reached the point of dramatic noise or detectable play presents a decision point. The bearing is not yet dangerous but it is deteriorating. At Shaw’s, we measure the play and assess the noise pattern, then give a clear recommendation: replace now, or monitor to the next service. We do not advise replacing a bearing that is not yet causing a problem — but we also do not recommend waiting on a bearing that has measurable play, because the deterioration from this point is typically faster than the rate that brought it here.

MOT implications

A wheel bearing with excessive play is a fail item at MOT. The tolerance is defined by the tester’s assessment of whether the play is slight, moderate or excessive, and whether it creates a safety concern. A bearing that has been left too long will also show scoring on the hub or hub carrier surface, which means the hub carrier itself may need replacing in addition to the bearing — a significantly more expensive repair. Replacing the bearing earlier avoids this progression.

Wheel bearing replacement at Shaw’s

Shaw’s replaces wheel bearings at both Kinmel Bay and Rhyl. On vehicles with hub assemblies rather than pressed bearings, the replacement is straightforward. On vehicles with pressed-in bearings, the correct press tools are required to avoid damaging the hub carrier during removal and installation.

Book a wheel bearing diagnosis at Shaw’s →

We check it properly. We explain it properly. We do the job properly. You decide what gets done.

Shaw’s Service Station | Kinmel Bay & Rhyl | 01745 353481