Parts for your 2015 Lexus Is-Gas struts

2015 Lexus IS gas-struts: what’s actually fitted

For the 2015 Lexus IS sedan (XE30 – IS250, IS350, IS300h), factory gas struts aren’t used on either the bonnet or the boot. Technical documentation backs this up: the Lexus Repair Manual (Lexus TIS) for GSE3#/AVE3# calls up a bonnet “support rod” (prop rod) rather than a gas spring, and the Toyota Electronic Parts Catalog for the same model lists a hood “stay” and shows no gas lift cylinder. At the rear, the luggage compartment uses gooseneck hinges and a torsion bar mechanism, not gas struts, as shown in the Lexus Genuine Parts Catalogue and body hardware diagrams.

Why skip gas struts on this model? It’s a mix of packaging, weight, cost, and durability priorities. A simple prop rod is lighter, cheaper, and extremely reliable across climates—ideal for a tightly packaged engine bay. For the boot, the gooseneck-plus-torsion setup gives consistent opening effort without the lifecycle or temperature-sensitivity issues that gas struts can have, while preserving sealing and NVH targets. These choices are common on premium sedans of the era and help keep service costs predictable.

Owners who prefer hands-free bonnet lifting can retrofit an aftermarket gas-strut kit designed for the XE30 IS. Reputable kits typically reuse existing mounting points or provide brackets to avoid drilling the bonnet skin. That said, any retrofit should be treated with care: the bonnet is aluminium on many trims, and incorrect mounting or over-pressured struts can affect panel alignment.

• Choosing a retrofit kit: Look for model-specific brackets, corrosion-resistant hardware, and strut forces spec’d for the IS bonnet (not just “generic”).
• Installation checks: Confirm clearance to the cowl, guards, and bonnet insulation through full travel, verify the bonnet latch engages cleanly.
• Care tips: Don’t lubricate the strut shafts—keep them clean and dry. Avoid solvent overspray. Replace in pairs if extension slows, they creak, or the bonnet sags when partly raised.
• Boot behaviour: Because the factory uses torsion bars, any boot “pop” can be tuned by adjusting bump stops or latch alignment, gas struts aren’t part of standard service items.

Bottom line: for a stock 2015 Lexus IS, “gas-struts” aren’t a factory serviceable part because they’re not fitted. If a previous owner installed aftermarket struts, treat them like any other wear item—inspect for leaks, corrosion, or weak lift and replace as a matched pair when tired.

• Does the 2015 Lexus IS have factory bonnet or boot gas struts?
  From Lexus TIS repair procedures and the Toyota EPC, the 2015 IS uses a bonnet prop rod and a torsion-bar boot hinge—no gas struts are fitted from factory on the sedan models.
• Can gas struts be retrofitted to the bonnet without drilling?
  Yes. Several kits supply brackets that use existing mounting points. Properly engineered kits avoid drilling the bonnet skin and maintain correct clearances and latch operation.
• How do you know aftermarket gas struts need replacing?
  If the bonnet no longer lifts smoothly, sags part-way, needs extra shove to open, or there’s oil mist on the strut body, they’re due. Replace both sides together to keep lift balanced.