WCFAB 2011-2016 LML Duramax 4" Intake Kit with Air BoxPowdercoat colors can be found here! WCFab 2011 2016 GM LML 6. 6L Duram" Intake Kit with Air Box. This high flow, fabricated aluminum intake pipe and air box enclosure with dry filter assembly replaces the restrictive plastic factory parts on your diesel for improved engine performance. All new design significantly increases air flow to your turbo producing improved horsepower and torque, quicker throttle response, and cooler intake temperatures by