Parts for your 2018 Mazda Bt-50-Rack boots

2018 Mazda BT-50 rack-boots: purpose, care and when to replace

Based on technical references including the Mazda BT-50 (UP/UR, 2011–2020) Workshop Manual’s Steering System section and the Mazda Electronic Parts Catalogue for Australia/New Zealand (Steering Gear group), the 2018 Mazda BT-50 uses a rack-and-pinion steering gear fitted with rack-boots (also called steering rack dust boots or bellows) on both ends of the rack. Major aftermarket catalogues for the BT-50 list these boots for 2011–2019 models as well. So rack-boots are absolutely relevant on a 2018 BT-50.

On a hardworking ute like the BT-50, rack-boots do a simple but vital job: they seal the ends of the steering rack, keeping dust, grit and water out while keeping lubricant in around the inner tie rods and rack bar. Off-road tracks, corrugations, beach runs and creek crossings throw all sorts at the front end, those rubber bellows act like a flexible barrier so the rack stays smooth, accurate and long-lived.

Because they cop heat, ozone and constant movement, rack-boots can harden, crack or split with age. Once a boot tears, moisture and fine grit can work their way onto the rack and inner tie rod, accelerating wear and corrosion. If hydraulic power steering fluid is seen inside a boot, that usually points to an internal rack seal leak—the boot itself isn’t meant to hold pressure or fluid, it just keeps contaminants out.

Good servicing for a 2018 BT-50 should include a quick look at both boots every service interval. A sensible cadence in Aussie and Kiwi conditions is every 10,000–15,000 km or at least annually, plus a check after deep water crossings or heavy off-road trips. Look for splits, perishing, loose clamps, wetness that smells like power steering fluid, or play at the inner tie rods. Catching a tired boot early is far cheaper than a steering rack replacement.

If a boot needs doing, it’s best practice to replace them in pairs using quality OE-style bellows and proper stainless ear clamps (skip generic zip-ties). The job typically involves removing the outer tie-rod end, sliding the old boot off, fitting the new boot without twisting, and re-clamping. Because the tie rod is disturbed, a wheel alignment should follow to keep tyres wearing evenly and steering tracking straight. After fitting, recheck clamp tension and boot seating at the next service, especially if the ute sees plenty of rough roads.

• Signs a BT-50 may need rack-boots: visible splits, grease or fluid weeping at the boot, notchy or vague steering, or a knock over bumps from inner tie rod wear.

Popular questions about 2018 Mazda BT-50 rack-boots

Do all 2018 BT-50 models have rack-boots?
Yes. The BT-50 uses a rack-and-pinion steering gear with a protective boot on each end of the rack. This is confirmed in the Mazda workshop documentation and the Mazda parts catalogue listings for the steering gear group on UP/UR series vehicles.

How often should the rack-boots be replaced on a BT-50?
There’s no fixed replacement age, they’re changed on condition. Inspect them every service or 10,000–15,000 km. If there’s cracking, a split, loose clamps or contamination inside, replace promptly and follow up with a wheel alignment.

Will torn rack-boots fail a WOF or RWC?
Quite possibly. In NZ a split steering boot can lead to a WOF fail, in Australia it can cause a roadworthy knock-back. Beyond compliance, a torn boot risks premature rack and inner tie-rod wear, so it’s worth sorting straight away.