Engine bay builds have a finishing point. There's a moment when you step back, look at everything under the bonnet, and either feel like it's done or feel like something is still missing. For a lot of GT-R and Silvia builds, that missing detail is the oil filler cap. Stock caps yellow with age, crack, lose their seal integrity, and look exactly like what they are — an overlooked factory part on a car that deserves better. The NISMO billet cap is the fix.

The NISMO Billet Aluminium Oil Filler Cap (15255-RN014) is precision-machined from billet aluminium, anodised for corrosion resistance, and carries the NISMO branding that signals the engine bay has been assembled with the right components. It fits the Skyline GT-R R32, R33, R34, Silvia S15, 350Z, and other Nissan applications sharing the same filler neck — which covers a large portion of the serious JDM sports car catalogue.

Beyond Appearance

The practical case for the NISMO cap isn't just visual. Stock oil filler caps on 30-year-old GT-Rs are often degraded — the rubber seal compresses, the plastic body develops cracks, and oil vapour escapes past the compromised seal into the engine bay. A billet cap with a fresh, properly specified seal addresses this. The NISMO unit seals consistently over far more thermal cycles than the original plastic cap was designed for.

This is the kind of component that makes mechanical sense and visual sense simultaneously. Add the NISMO Billet Oil Filler Cap to your next service order and cross one detail off the engine bay list permanently.