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HSP Diesel Max Flow Intake Mouthpiece For 04.5-10 Chevrolet And GMC LLY/LBZ/LMM Duramax With 4 Inch Aftermarket Intakes Kingsport Grey
SKU: 003-4-HSP-DG-GVJG
$398.62 CAD
Shipping calculated at checkout.
The factory turbo inlet mouthpiece not only lacks style - it also restricts airflow and limits your engine's power potential. The HSP Max Flow Mouthpiece solves both issues using a cast-aluminum, CNC-machined design engineered for durability, airflow, and improved sealing.
Featuring an integrated O-ring flange to prevent unfiltered air leaks and a 1/2 inch NPT port in the PCV location, this mouthpiece ensures that your aftermarket intake system is not held back by a restrictive OEM component. The 4.5 inch inlet guarantees maximum flow before reducing to your 4 inch aftermarket intake.
Included Components:
- Max Flow Intake Mouthpiece For 04.5-10 Chevrolet And GMC LLY/LBZ/LMM Duramax With 4 Inch Aftermarket Intakes Kingsport Grey
- 1x 4.5 inch Max Flow Mouthpiece
- 1x 1/2 inch NPT Plug
- 1x 4.5 inch to 4 inch Reducer Boot (for 4 inch aftermarket intakes)
- 1x 4.5 inch Stainless Steel T-Bolt Clamp
- 1x 4 inch Stainless Steel T-Bolt Clamp
- 1x O-Ring Seal
Vehicle Fitment:
- LLY: 2004.5-2005 (VIN Code 2) with 4 inch LBZ-style aftermarket intake
- LBZ: 2006-2007 (VIN Code 2 or D) with 4 inch aftermarket intake
- LMM: 2007.5-2010 (VIN Code 6) with 4 inch aftermarket intake
Special Fitment Notes:
- This mouthpiece will not fit with factory air intake systems.
- For HSP Intakes, please see 003-HSP.
How to Identify VIN Code:
- The engine code is determined by the 8th character of the VIN number.
- The model year is identified by the 10th character.
HSP No BS Limited Lifetime Warranty
At HSP, we believe in our products and stand firmly behind every one that leaves our facility. For years, we've gone above and beyond for our customers - even without a formal policy. With the HSP No BS inch Limited Lifetime Warranty, that same commitment is now set in stone, providing clarity, dependability, and support throughout ownership.
questions we get about hsp diesel daily:
Who is HSP Diesel and what makes their products different?
HSP Diesel builds high-flow, made-in-the-USA diesel performance hard parts that solve real-world airflow restrictions. Their components are CAD-designed, flow-tested, and engineered for durability, clean fitment, and consistent performance. Customers choose HSP because the quality, welds, powder coat options, and fitment are more refined than generic diesel aftermarket parts.
Are HSP Diesel products compatible with my truck?
Most HSP Diesel components are designed for GM Duramax platforms (LB7, LLY, LBZ, LMM, LML, L5P). Each product page lists exact year and engine compatibility. If you're not sure which Duramax engine you have, send us your VIN and we’ll gladly confirm fitment before you order.
Do HSP Diesel parts improve performance?
Yes. Upgrades like intercooler pipes, Y-bridges, turbo inlet kits, and intakes dramatically reduce airflow restriction. Most owners see faster spool, cooler EGTs, smoother towing performance, and better throttle response—even on otherwise stock trucks.
Do I need tuning after installing HSP Diesel parts?
Most HSP airflow parts (intakes, charge pipes, Y-bridges, turbo mouthpieces) do not require tuning to install or drive. However, a tune may help the truck take full advantage of the increased airflow. If a part requires tuning—such as a turbo upgrade—the product page will clearly note it.
Are HSP Diesel parts emissions compliant?
Many HSP Diesel components work with factory emissions systems in place. Some turbo-related or race-use parts may not be emissions compliant. Always read the emissions note on the product page and follow local laws before installation.
How long does it take for HSP Diesel parts to ship?
Most HSP parts are built and powder-coated after you order. Standard colors ship sooner, while custom colors may require 2–4+ weeks depending on workload. Lead times are shown on each product page and updated frequently.
What powder coat colors are available?
HSP offers a wide range of standard colors (black, red, white, blue, etc.) plus custom powder coat finishes. Custom colors may add cost and lead time. If you're trying to match an existing part, send us a photo and we can help you choose the closest match.
Do HSP Diesel kits come with everything needed for installation?
Most HSP parts include the clamps, boots, brackets, and hardware required for a clean install. Larger systems—like turbo kits or intercooler upgrades—may require additional supporting parts. Each product page lists everything included in the kit.
Are HSP Diesel parts compatible with other aftermarket brands?
In most cases, yes. As long as the parts use compatible diameters and mounting points, HSP Diesel components integrate well with other brands of turbos, intakes, intercooler systems, and fueling components. If you already have mods installed, tell us what’s on the truck and we’ll check compatibility.
Will HSP Diesel parts help with towing?
Absolutely. Improved airflow reduces EGTs, increases turbo response, and helps the truck pull more consistently under load. Many daily drivers and towing-focused Duramax owners upgrade to HSP specifically for cooling and drivability gains.
What warranty do HSP Diesel products include?
HSP Diesel provides a warranty against workmanship and material defects. If a part arrives damaged or defective, contact us with photos and your order number and we’ll assist in getting it corrected.
Can I install HSP Diesel parts myself?
Many components—like charge pipes, intakes, and coolant tanks—are DIY-friendly. More complex installs (Y-bridges, turbo kits, or tight-tolerance piping) may require professional installation. Review the instructions to make sure you're comfortable with the job.
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