Parts for your 2007 Toyota Mark x-Rack boots

2007 Toyota Mark X rack boots: what they do and when to replace them

Technical sources confirm the 2007 Toyota Mark X (GRX120/GRX121 series) uses rack-and-pinion steering with rack boots fitted on both ends of the steering gear. The Toyota Electronic Parts Catalogue (EPC) for GRX120/121 lists a “Boot, Steering Rack” with clamps as part of the steering gear sub‑assembly, and Toyota’s Technical Information System (TIS) service procedures specify inspection of the rack boots during routine maintenance. Whether the Mark X is hydraulic-assist or electric-assist, the rack ends are protected by flexible bellows-style boots.

On this Mark X, the rack boots (often called bellows) are the flexible covers that seal each end of the steering rack. Their job is simple but critical: keep dust, water, and grit out of the rack-and-pinion and inner tie-rod joints, while letting the steering move freely. If a boot splits, contaminants get in, grease gets out, and wear accelerates fast. On hydraulic racks, a torn boot can also mask a leaking inner rack seal by trapping power steering fluid.

Servicing-wise, the boots deserve a quick look at every service or WoF/RWC check. Owners and technicians should look for cracking, oiliness, or a loose clamp. Any tear, even a small one, is a replace-now item. Leaving it will usually lead to inner tie-rod play, notchy steering, or premature rack failure—none of which is kind to the wallet.

• Best practice is to replace boots in pairs and use new clamps to ensure a proper seal.
• If a boot is oily inside, check for a power steering rack seal leak before refitting.
• Inspect the inner tie-rod ball joint while the boot is off, replace if there’s any free play.
• A wheel alignment is recommended after boot replacement because the outer tie-rod end is removed.

Quality matters. Genuine or reputable aftermarket boots made from OE-grade rubber or thermoplastic last longer, particularly in Aussie and Kiwi climates where heat, UV and unsealed roads can be tough on rubber. Many Mark X examples still on the road are well over 100,000 km, by that age, original boots are often perished. A fresh set of boots is affordable insurance that keeps the steering tight, protects the rack, and helps the vehicle sail through its next inspection.

Popular questions about 2007 Toyota Mark X rack boots

How often should rack boots be replaced on a Mark X?
There’s no fixed kilometre interval. They’re inspected at each service and replaced on condition. In typical AU/NZ use, original boots often harden and crack after 8–12 years. If there’s any split, brittleness, or oil contamination, replacement is due.

Can the rack boots be replaced without removing the steering rack?
Yes. The usual method is to remove the outer tie-rod end, slide off the old boot, clean and inspect the inner joint, then fit the new boot with fresh clamps. Because toe can change when the tie-rod end is disturbed, a wheel alignment is recommended.

What are the signs a rack boot has failed?
Visible cracks or a torn bellows, grease or grit inside the boot, damp or oily residue (on hydraulic racks), and developing inner tie-rod play. Left unattended, it can lead to clunks, uneven tyre wear, vague steering, and a failed WoF/RWC.