15- 4 Runner 4.0L Air Intake Kit

The 15–4 Runner 4.0L Air Intake Kit by K&N Engineering is purpose-built for fourth-generation Toyota 4Runner owners seeking measurable gains in throttle response and engine efficiency. This cold-air intake system is engineered for drivers who understand that unrestricted airflow directly translates to improved combustion efficiency and noticeable performance enhancement. Whether you're tackling technical terrain or highway cruising, upgrading from the OEM restrictive intake manifold design gives your 4.0-liter V6 the breathing room it demands.

K&N's proven air intake architecture draws cooler, denser air from the fender well directly into the engine bay, bypassing the factory airbox's restrictive design. The kit features K&N's signature high-flow air filter media, which maintains excellent filtration while reducing intake restriction compared to stock paper filters. The system's precision-engineered tubing minimizes turbulence and pressure losses throughout the intake tract, allowing the 4.0L engine to achieve its full volumetric efficiency potential. Installation is straightforward for mechanically inclined owners, with all necessary components and hardware included in the 13.6-pound package.

This kit is ideal for 2010–2015 4Runner owners who want a bolt-on modification without ECU tuning or major fabrication work. Real-world users report improved engine responsiveness, particularly in mid-range acceleration where the 4.0L V6 operates most frequently during daily driving and off-road work. The K&N air intake is compatible with stock exhaust and emission systems, making it a straightforward first modification that pairs well with future upgrades like cat-back exhaust systems or throttle body spacers for cumulative gains.