Parts for your 2021 Mazda 3-Rack boots

2021 Mazda 3 rack boots — what they do and when to replace them

Based on the Mazda Workshop Manual for the BP-platform Mazda 3 (Steering System — Steering Gear and Linkage) and Mazda’s Electronic Parts Catalogue for 2019–2023 BP models, the 2021 Mazda 3 uses steering rack dust boots (often called rack boots or bellows) on both ends of its electric power steering (EPS) rack. OE and aftermarket parts catalogues across Australia and New Zealand also list specific rack boot kits for this model, confirming they’re very much relevant and fitted.

On the 2021 Mazda 3, the rack boots sit over the inner tie rods and the ends of the steering rack, acting like flexible bellows. Their job is to keep water, road grit, and dust away from the rack bar and inner tie rod joints while allowing the rack to move freely lock-to-lock. They also help the rack “breathe” as the volume inside the bellows changes, which stops pressure spikes that could stress the seals. Even though the BP Mazda 3 uses electric, not hydraulic, assist, the rack still relies on those boots to keep contaminants out and the steering feeling tight and precise.

During routine servicing, a quick visual check of the rack boots is smart practice. A technician will look for splits, perishing, or unsecured clamps, and for tell-tale grease fling on the inner rims or underbody. If a boot’s torn, water can track into the rack, corroding the rack bar and inner tie rod, and in a worst case upsetting EPS performance. In both Australia and New Zealand, damaged or insecure rack boots can lead to a roadworthy/WOF fail.

If replacement’s needed, it’s good form to do both sides as a pair. The outer tie rod end is usually removed to slide the new boot on, so a wheel alignment is recommended afterwards to keep tyres wearing evenly. Tips the pros follow:

• Use OE-style bands or quality clamps, not generic cable ties.
• Fit the boot without twists and seat it fully in the rack and tie-rod grooves.
• Don’t overpack with grease, follow the workshop manual’s guidance.
• Keep EPS wiring and sensors undisturbed, torque fasteners to spec.

There’s no fixed kilometre-based interval to replace rack boots, they’re a condition-based item. Have them inspected at every service (typically 10,000–15,000 km or 12 months), especially if the car sees rough roads, frequent kerb strikes, or floodwater. Catching a small split early is far cheaper than a steering rack replacement down the track.

Popular questions

Does a 2021 Mazda 3 have rack boots?
Yes. Technical documentation for the BP-platform Mazda 3 and OEM parts catalogues confirm two steering rack dust boots are fitted to the EPS rack.

How often should the rack boots be checked or replaced?
Check at every service. Replace immediately if a boot is split, perished, or the clamps are loose. There’s no set interval — it’s condition-based.

Do they need a wheel alignment after replacing a rack boot?
Usually, yes. If the tie rod end is removed to fit the new boot, a wheel alignment is recommended to protect tyre life and steering feel.