Parts for your 2015 Lexus Is-Rack boots

2015 Lexus IS rack-boots: what they do and when to replace them

Rack-boots (also called steering rack bellows) are absolutely used on the 2015 Lexus IS range (XE30 series, including IS 250, IS 350 and IS 300h). Lexus’ factory repair manual for the XE30 steering gear assembly shows the boot, clamps and inner tie rod as serviceable items, and the Toyota/Lexus Electronic Parts Catalogue lists a “steering gear boot” for these models. Even though the 2015 IS uses electric power steering (rack-assist EPS), the rack-and-pinion still relies on flexible boots to keep dust and water out of the inner tie rods and rack ends.

On this Lexus, the rack-boots are there to protect the moving joints from grit, moisture and road grime. They keep grease where it belongs and stop contaminants from chewing out the inner tie rod ball sockets and rack seals. Because it’s EPS, there’s no hydraulic fluid running through the rack, so a wet boot isn’t power-steering oil — it’s usually split-boot ingress or grease migrating from the inner tie rod.

Typical reasons owners replace the boots on a 2015 IS:

• Tears, perishing or cracked rubber/thermoplastic
• Loose or missing boot clamps
• Grit or water found inside the boot, or knocking from a worn inner tie rod
• WOF/RWC defect for a split or unsecured steering boot

Good practice for servicing this model:

• Inspect both boots at every service interval (around 10,000–15,000 km or 12 months).
• If one boot is damaged, consider replacing both sides — they age together.
• Use quality OEM-equivalent boots and single-use clamps, cable ties aren’t acceptable.
• After boot or inner tie rod work, get a wheel alignment — toe will usually change.
• If a boot has been split for a while, check the inner tie rod for play and the rack for corrosion before refitting.

Replacement is straightforward in experienced hands: the tie rod end is removed, the old boot and clamps come off, the area is cleaned, a light smear of the correct grease is applied to the inner joint, and the new boot is seated and clamped without twisting. A careful tech will clock the tie rod end to maintain toe roughly, but an alignment is still the go. Expect more frequent checks if the vehicle sees gravel roads, coastal exposure or regular underbody washing, as these can accelerate boot cracking.

Popular questions about 2015 Lexus IS rack-boots

Do all 2015 Lexus IS models have rack-boots?
Yes. The XE30 IS range (IS 250, IS 350 and IS 300h) uses an electric rack-and-pinion steering gear that includes protective rack-boots. This is shown in the Lexus repair manual’s steering gear diagrams and the Toyota/Lexus parts catalogue entries.

How often should the rack-boots be replaced?
There’s no fixed kilometre age — they’re replaced on condition. Have them inspected at each service. If they’re split, perished or the clamps are dodgy, replace them immediately to protect the inner tie rods and rack.

Can driving with a torn rack-boot damage the steering rack?
It can. A torn boot lets grit and water in, which can wear the inner tie rod joint and corrode rack components. Leaving it too long can turn a simple boot job into inner tie rod or rack repairs, plus a mandatory wheel alignment.