Review on K&N Engine Air Filter: Premium Performance Replacement (Land Cruiser, Tundra, Sequoia, LX 570) by Scott Vazquez

Better gas mileage is a big plus in the 5.7 Tundra. Skip the expensive tricks of blowing cold air. The car already has one, it just needs to breathe better. On Toyota vehicles, remove the secondary filter and order a rubber O-ring to replace the wire mesh on the air hose to the throttle body. The whistle comes from the "if you don't like it" screen. Throttle body gaskets aren't effective, add a looser exhaust "I recommend Gibson as I love it" and there it is. An engine that can feed air and exhaust gases more easily is more efficient. The increase in performance is noticeable. Gas mileage on my Tundy is 18.2 to 21.5 highway. I hope this helps you get the performance gain, fuel economy and money savings you want.