Wehrli 100535 4 inch Intake Horn | 2001-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

Features:

• Compatible with 2001-2004 LB7 Duramax
• 4 inch high-flow intake horn
• Works with factory or upgraded IHI turbos
• Fits OEM and aftermarket intake systems
• Improves turbo spool-up and throttle response
• Gains up to 20 horsepower with upgrades
• No tuning required for installation
• Includes stainless hardware and gasket
• Durable powder-coated finish resists corrosion
• Designed for direct bolt-on installation
• Great for performance or daily driving
• Built for improved intake efficiency

Let Your Turbo Breathe And Unleash Real Power

If you're looking to get more out of your 2001-2004 Duramax LB7, swapping in the Wehrli 4 inch Intake Horn is one of those upgrades that just makes sense. It’s built to deliver better airflow right where your turbo needs it most, helping your truck spool faster and run smoother. The added throttle response is something you’ll notice right away, especially when towing, accelerating, or just getting off the line quicker. This is a no-tuning-required mod, so you can bolt it on and hit the road without messing with your ECM. Whether you’re running the factory IHI turbo or an upgraded drop-in version, this horn is ready to work with your setup. It fits both stock and aftermarket intake systems, giving you flexibility no matter what stage your build is in. With up to 20 horsepower gains possible when paired with other performance upgrades, it’s a solid investment that pays off every time you press the pedal.

Engineered To Deliver Consistent Airflow And Clean Fitment

The Wehrli 100535 4 inch Intake Horn is precision-built for Duramax LB7 applications and designed to streamline airflow between your intake system and turbocharger. Its larger internal diameter allows for smoother, higher-volume air delivery, which directly supports quicker turbo response and improved engine performance. The horn is compatible with both OEM and aftermarket intake systems, as well as factory or upgraded IHI turbos, making it a versatile option for a wide range of builds. It includes stainless steel hardware and a gasket for a secure, leak-free fit and is powder-coated for durability and resistance to corrosion. Since tuning isn’t required for installation, this part provides measurable gains without additional electronics or calibration. On max-effort or heavily tuned setups, users have reported power increases of 10 to 15 horsepower, and up to 20 horsepower with upgraded turbos. It’s a clean, efficient upgrade that helps maximize your engine’s breathing capability while maintaining factory-like reliability.

Fits: 2001, 2002, 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7

Notes:

• Fits 2001-2004 GM 6.6L Duramax LB7 engines only
• Compatible with factory and upgraded IHI turbos
• Works with OEM and aftermarket intake systems
• No tuning required for installation or use
• Designed to replace the factory turbo intake horn
• Ideal for performance upgrades or high-flow builds
• Includes stainless hardware and gasket for installation
• Powder coated for long-lasting durability and finish
• Can provide horsepower gains with other performance parts
• Ensure proper fitment with turbo and intake setup before ordering