The AEM 21-681C Performance Cold Air Intake System produces horsepower and torque gains by replacing your vehicle's restrictive factory air filter and air intake housing. This air intake system was designed, tuned and dyno-tested to fit specific Audi A4 models. Air enters the system through an oversized AEM Dryflow synthetic washable air filter for outstanding air flow, filtration and performance. The air filter is located in the original air box space and is protected by a heat shield which is designed to reduce intake air temperature and increase horsepower. The intake tubing is constructed from mandrel-bent aluminum featuring a durable gunmetal gray powder coated finish. This air intake system was developed to accommodate the engine's factory emissions control devices including the mass air flow sensor. The cylinder shaped AEM Dryflow air filter is made from an oil-free, synthetic filter media that can be used for up to 100,000 miles before cleaning is needed (depending on driving conditions). The air intake system is backed by AEM's Lifetime Limited Warranty. Some AEM air intakes are not legal for sale or use in California and other states adopting California emission standards while others are 50 state legal. View the 21-681C vehicle applications to determine the legal status for each vehicle.
Installation Instructions
User 1
This Part Fits:
Installation Instructions
User 1
This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2002-2006 | Cadillac | Escalade | Base |
| 2003-2006 | Cadillac | Escalade ESV | Base |
| 2002-2006 | Cadillac | Escalade EXT | Base |
| 2002-2005 | Chevrolet | Avalanche 1500 | Base |
| 2005-2006 | Chevrolet | Avalanche 1500 | LS |
| 2005-2006 | Chevrolet | Avalanche 1500 | LT |
| 2002-2003 | Chevrolet | Avalanche 1500 | North Face |
| 2002-2003 | Chevrolet | Avalanche 1500 | On Road Edition |
| 2003 | Chevrolet | Avalanche 1500 | WBH |
| 2004-2006 | Chevrolet | Avalanche 1500 | Z66 |
| 2002-2006 | Chevrolet | Avalanche 1500 | Z71 |
| 1999-2005 | Chevrolet | Silverado 1500 | Base |
| 2004-2006 | Chevrolet | Silverado 1500 | Hybrid |
| 1999-2006 | Chevrolet | Silverado 1500 | LS |
| 1999-2006 | Chevrolet | Silverado 1500 | LT |
| 2003-2006 | Chevrolet | Silverado 1500 | SS |
| 2002-2006 | Chevrolet | Silverado 1500 | WT |
| 2004-2005 | Chevrolet | Silverado 1500 | Z71 Off-Road |
| 2007 | Chevrolet | Silverado 1500 Classic | Hybrid |
| 2007 | Chevrolet | Silverado 1500 Classic | LS |
| 2007 | Chevrolet | Silverado 1500 Classic | LT |
| 2007 | Chevrolet | Silverado 1500 Classic | SS |
| 2007 | Chevrolet | Silverado 1500 Classic | WT |
| 2005 | Chevrolet | Silverado 1500 HD | Base |
| 2001-2003,2005 | Chevrolet | Silverado 1500 HD | LS |
| 2001-2003,2005-2006 | Chevrolet | Silverado 1500 HD | LT |
| 2007 | Chevrolet | Silverado 1500 HD Classic | LT |
| 1999-2004 | Chevrolet | Silverado 2500 | Base |
| 1999-2004 | Chevrolet | Silverado 2500 | LS |
| 1999-2004 | Chevrolet | Silverado 2500 | LT |
| 2004 | Chevrolet | Silverado 2500 | WT |
| 2001-2005 | Chevrolet | Silverado 2500 HD | Base |
| 2001-2006 | Chevrolet | Silverado 2500 HD | LS |
| 2001-2006 | Chevrolet | Silverado 2500 HD | LT |
| 2003-2006 | Chevrolet | Silverado 2500 HD | WT |
| 2007 | Chevrolet | Silverado 2500 HD Classic | LS |
| 2007 | Chevrolet | Silverado 2500 HD Classic | LT |
| 2007 | Chevrolet | Silverado 2500 HD Classic | WT |
| 2001-2005 | Chevrolet | Silverado 3500 | Base |
| 2001-2006 | Chevrolet | Silverado 3500 | LS |
| 2001-2006 | Chevrolet | Silverado 3500 | LT |
| 2004,2006 | Chevrolet | Silverado 3500 | WT |
| 2000-2001,2006 | Chevrolet | Suburban 1500 | Base |
| 2000-2006 | Chevrolet | Suburban 1500 | LS |
| 2000-2006 | Chevrolet | Suburban 1500 | LT |
| 2006 | Chevrolet | Suburban 1500 | LTZ |
| 2002-2006 | Chevrolet | Suburban 1500 | Z71 |
| 2000-2001 | Chevrolet | Suburban 2500 | Base |
| 2000-2006 | Chevrolet | Suburban 2500 | LS |
| 2000-2006 | Chevrolet | Suburban 2500 | LT |
| 2000-2001,2006 | Chevrolet | Tahoe | Base |
| 2000-2006 | Chevrolet | Tahoe | LS |
| 2000-2006 | Chevrolet | Tahoe | LT |
| 2002-2006 | Chevrolet | Tahoe | Z71 |
| 2002-2005 | GMC | Sierra 1500 | Base |
| 2001 | GMC | Sierra 1500 | C3 |
| 2002-2006 | GMC | Sierra 1500 | Denali |
| 2002 | GMC | Sierra 1500 | HT |
| 2005-2006 | GMC | Sierra 1500 | Hybrid |
| 1999-2003,2006 | GMC | Sierra 1500 | SL |
| 1999-2006 | GMC | Sierra 1500 | SLE |
| 1999-2006 | GMC | Sierra 1500 | SLT |
| 2002-2006 | GMC | Sierra 1500 | WT |
| 2007 | GMC | Sierra 1500 Classic | Denali |
| 2007 | GMC | Sierra 1500 Classic | Hybrid |
| 2007 | GMC | Sierra 1500 Classic | SL |
| 2007 | GMC | Sierra 1500 Classic | SLE |
| 2007 | GMC | Sierra 1500 Classic | SLT |
| 2007 | GMC | Sierra 1500 Classic | WT |
| 2001-2003,2005-2006 | GMC | Sierra 1500 HD | SLE |
| 2001-2003,2005-2006 | GMC | Sierra 1500 HD | SLT |
| 2007 | GMC | Sierra 1500 HD Classic | SLE |
| 2007 | GMC | Sierra 1500 HD Classic | SLT |
| 2002-2004 | GMC | Sierra 2500 | Base |
| 1999-2002 | GMC | Sierra 2500 | SL |
| 1999-2004 | GMC | Sierra 2500 | SLE |
| 1999-2004 | GMC | Sierra 2500 | SLT |
| 2003-2004 | GMC | Sierra 2500 | WT |
| 2002-2005 | GMC | Sierra 2500 HD | Base |
| 2001-2002,2006 | GMC | Sierra 2500 HD | SL |
| 2001-2006 | GMC | Sierra 2500 HD | SLE |
| 2001-2006 | GMC | Sierra 2500 HD | SLT |
| 2003-2006 | GMC | Sierra 2500 HD | WT |
| 2007 | GMC | Sierra 2500 HD Classic | SL |
| 2007 | GMC | Sierra 2500 HD Classic | SLE |
| 2007 | GMC | Sierra 2500 HD Classic | SLT |
| 2007 | GMC | Sierra 2500 HD Classic | WT |
| 2002-2005 | GMC | Sierra 3500 | Base |
| 2001-2002,2006 | GMC | Sierra 3500 | SL |
| 2001-2006 | GMC | Sierra 3500 | SLE |
| 2001-2006 | GMC | Sierra 3500 | SLT |
| 2004-2006 | GMC | Sierra 3500 | WT |
| 2007 | GMC | Sierra 3500 Classic | SL |
| 2007 | GMC | Sierra 3500 Classic | SLE |
| 2007 | GMC | Sierra 3500 Classic | SLT |
| 2007 | GMC | Sierra 3500 Classic | WT |
| 2001-2006 | GMC | Yukon | Denali |
| 2006 | GMC | Yukon | SL |
| 2000-2006 | GMC | Yukon | SLE |
| 2000-2006 | GMC | Yukon | SLT |
| 2001-2006 | GMC | Yukon XL 1500 | Denali |
| 2006 | GMC | Yukon XL 1500 | SL |
| 2002-2006 | GMC | Yukon XL 1500 | SLE |
| 2002-2006 | GMC | Yukon XL 1500 | SLT |
| 2000-2006 | GMC | Yukon XL 2500 | SLE |
| 2000-2006 | GMC | Yukon XL 2500 | SLT |