Parts for your 2020 Mazda 3-Wheel hubs

2020 Mazda 3 wheel-hubs: what they do and when to replace them

Technical references including the Mazda Workshop Manual for the BP-series Mazda 3 (Front/Rear Axle and Hub sections) and the Mazda Electronic Parts Catalogue confirm that the 2020 Mazda 3 is fitted with sealed wheel hub-and-bearing assemblies at each corner, incorporating the wheel speed (ABS) encoder. So wheel-hubs are absolutely relevant to this model.

On the 2020 Mazda 3, the hub assembly is the bit that the wheel bolts onto and the brake rotor hangs off. Inside the hub is a precision, sealed bearing that supports the vehicle’s weight and lets the wheel spin smoothly with minimal friction. It also houses the encoder that feeds wheel speed info to the ABS and stability systems. At the front, the hub centres and supports the drive shaft, at the rear it keeps the wheel true to prevent wobble and uneven tyre wear.

There’s no scheduled greasing or adjustment on these sealed units. Instead, they’re inspected during routine servicing for noise, play and smooth rotation. Replacement is typically only needed when there’s wear or damage from high kilometres, harsh roads, kerb strikes, water ingress or improper wheel nut torque.

• Common symptoms of a failing hub: a humming or droning that rises with speed, a change in noise when gently loading one side in a lane change, ABS warning light or erratic speed readings, play felt at 12 and 6 o’clock on the tyre, uneven tyre wear or mild steering vibration.

• Service tips: keep the hub face clean when changing wheels to prevent rotor/wheel runout, always torque wheel nuts to the spec in the owner’s manual, avoid pressure-washing directly into the hub area, after deep water crossings, have the hubs checked if any noise appears.

When replacement is due, the workshop will swap the hub assembly rather than trying to service the bearing. It’s smart to choose quality parts that match the ABS encoder type for the BP Mazda 3. New axle/hub nuts and certain bolts are often single-use—follow Mazda’s torque and replacement guidance in the workshop manual. After the job, a road test and, if needed, a wheel alignment check help ensure quiet running and even tyre wear.

Popular questions

Does the 2020 Mazda 3 have serviceable wheel bearings?
Yes, but not in the old-school sense. The BP Mazda 3 uses sealed hub-and-bearing units. They’re not greased or adjusted, the whole hub assembly is replaced if worn or noisy. This design improves durability and keeps contaminants out.

How can someone tell if a wheel-hub needs replacing on a 2020 Mazda 3?
Listen for a speed-dependent hum or droning that shifts when gently steering left or right. Check for play by rocking the wheel at 12 and 6 o’clock, watch for an ABS light, and feel for roughness when the wheel is spun off the ground. Any of these signs warrants a professional inspection.

Is it safe to drive with a noisy hub on a Mazda 3?
It’s not recommended. Continued driving can worsen wear, affect braking via ABS behaviour, and in extreme cases risk bearing seizure. It’s best to book the repair promptly to protect tyres, brakes and safety systems.