HSP Diesel Max Flow Intake Mouthpiece For 2004.5-2010 Chevrolet And GMC LLY / LBZ / LMM Duramax With 4IN Aftermarket Intakes

Name: HSP Diesel Max Flow Intake Mouthpiece For 2004.5-2010 Chevrolet And GMC LLY / LBZ / LMM Duramax With 4IN Aftermarket Intakes
Brand: HSP
SKU: 003-4-HSP
Price: 320 USD
Availability: InStock

As low as: $320.00

HSP Diesel Max Flow Intake Mouthpiece For 2004.5-2010 Chevrolet And GMC LLY / LBZ / LMM Duramax

Ships in 2 - 3 Weeks

SKU: 003-4-HSP

SKU: 003-4-HSP
HSP Material: Aluminized Steel

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Fitment

LLY: 04.5–05 (VIN Code 2) with 4” LBZ style aftermarket intake
LBZ: 06–07 (VIN Code 2 or D) with 4” aftermarket intake
LMM: 07.5–10 (VIN Code 6) with 4” aftermarket intake

What's Included

1x 4.5” Max Flow Mouthpiece)
1x 1/2IN NPT plug
1x 4.5IN to 4IN reducer boot for aftermarket 4” intakes
1x 4.5IN Stainless steel t-bolt clamp
1X 4IN Stainless steel t-bolt clamp
1x O ring seal

HSP Turbo Inlet Max Flow Mouthpiece for 2004.5–2010 Chevrolet / GMC Duramax LLY / LBZ / LMM (for 4” Aftermarket Intakes)

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 ½— 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— inlet guarantees maximum flow before reducing to your 4— aftermarket intake.

Included Components

1x 4.5— Max Flow Mouthpiece
1x ½— NPT Plug
1x 4.5— to 4— Reducer Boot (for 4— aftermarket intakes)
1x 4.5— Stainless Steel T-Bolt Clamp
1x 4— Stainless Steel T-Bolt Clamp
1x O-Ring Seal

Vehicle Fitment

LLY: 2004.5–2005 (VIN Code 2) with 4— LBZ-style aftermarket intake
LBZ: 2006–2007 (VIN Code 2 or D) with 4” aftermarket intake
LMM: 2007.5–2010 (VIN Code 6) with 4” 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.

Our Warranty

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— Limited Lifetime Warranty, that same commitment is now set in stone, providing clarity, dependability, and support throughout ownership.

For more information about our Lifetime, No BS Warranty, click HERE.

Customer Questions

Yes. It fits 2007.5–2010 LMM Duramax trucks (VIN Code 6) when used with a 4-inch aftermarket intake.

The HSP Max Flow Intake Mouthpiece fits 2004.5–2010 Chevrolet and GMC Duramax trucks, including LLY (2004.5–2005), LBZ (2006–2007), and LMM (2007.5–2010), when paired with a 4-inch LBZ-style aftermarket intake. Fitment is determined by the engine VIN code.

Yes. This mouthpiece fits 2004.5–2005 LLY Duramax trucks (VIN Code 2) as long as the truck is running a 4-inch LBZ-style aftermarket intake.

Yes. This intake mouthpiece fits 2006–2007 LBZ Duramax trucks (VIN Code 2 or D) when used with a 4-inch aftermarket intake.

No. This mouthpiece will not fit factory air intake systems. It is designed specifically for trucks running a 4-inch aftermarket intake.

A turbo inlet mouthpiece connects the intake tube to the turbocharger inlet. On LLY, LBZ, and LMM Duramax trucks, upgrading the mouthpiece can reduce restriction before the turbo, improve airflow consistency, and help prevent unfiltered air leaks at the turbo connection.

The factory mouthpiece can restrict airflow and may not seal as well under load. The HSP Max Flow Mouthpiece uses a larger 4.5-inch inlet and an O-ring–sealed flange to improve flow and sealing, supporting better turbo efficiency and throttle response.

This mouthpiece is cast aluminum with CNC-machined sealing surfaces, uses an integrated O-ring flange to prevent unfiltered air leaks, and features a 4.5-inch inlet that transitions to a 4-inch aftermarket intake for improved airflow compared to the OEM inlet design.

It can support horsepower and throttle response gains by reducing inlet restriction and improving airflow into the turbo, especially on trucks with additional airflow or tuning upgrades. Actual gains vary by setup.

The mouthpiece includes a 1/2-inch NPT port located in the PCV location. It can be used for certain PCV routing configurations or plugged using the included 1/2-inch NPT plug, depending on your setup.

The kit includes the 4.5-inch Max Flow Mouthpiece, a 1/2-inch NPT plug, a 4.5-inch to 4-inch reducer boot, one 4.5-inch stainless T-bolt clamp, one 4-inch stainless T-bolt clamp, and an O-ring seal.

Not this specific version. This mouthpiece is designed for 4-inch aftermarket intakes. For HSP intake compatibility, the product notes specify using 003-HSP instead.

The engine code is determined by the 8th character of your VIN, and the model year is identified by the 10th character. This helps confirm whether your truck is LLY, LBZ, or LMM.

Installation is designed to be bolt-on for the listed Duramax platforms when the truck has the correct 4-inch aftermarket intake. No custom fabrication is typically required.

Yes. The integrated O-ring seal helps prevent unfiltered air leaks at the turbo inlet connection, improving sealing integrity compared to many factory-style connections.

Yes. Improving inlet airflow and sealing is beneficial for daily driving and towing because it supports consistent turbo performance and helps reduce the chance of intake leaks over time.

Yes. It is backed by the HSP No BS Limited Lifetime Warranty, covering manufacturing defects and providing long-term support.

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