Review on Airaid Cold Air Intake System: Boost Your TOYOTA's Horsepower with Superior Filtration - Compatible with 2010-2020 4 Runner and FJ Cruiser (AIR-511-302) by Seth Hogate

I installed this on my 2015 4runner along with an Airid throttle body gasket. Installation took about an hour, should have been less, but it took longer due to the bolt holes on my truck. They are using an existing hole not being used for utilities, the shaft was not fully drilled through and there was still metal at the bottom. Anyway, the installation was easy, in the cockpit you can hear a slight noise when you let off the gas, but nothing unbearable. In terms of performance, it doesn't make a huge difference to me, so don't expect to throw that in and get a shocking performance boost. As far as gas mileage goes with the throttle body spacer I've gone from a steady 18mpg to the current 20-21, which isn't much but there's a difference and I'll take what I can. Others claim mileage has decreased, but mentally you add power changes and your leg gets heavier, resulting in better fuel economy. If you have money to spare and it will make you happy, then I say go for it.