HSP Diesel One Piece Thermostat Housing Kit For 2001-2005 Chevrolet And GMC LB7 / LLY Duramax
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Colours and prices as published by HSP Diesel · verified 9/8/2026
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HSP One Piece Thermostat Housing Kit for 2001–2005 Chevrolet / GMC Duramax LB7 / LLY The 040-HSP One Piece Thermostat Housing Kit is designed for 2001–2005 Chevrolet and GMC Duramax LB7 and LLY trucks. This forward-facing thermostat housing is a major upgrade for trucks running aftermarket turbos, dual CP3 systems, or custom engine bay layouts. It simplifies coolant routing, increases under-hood clearance, and dramatically improves serviceability and aesthetics. Why Choose the HSP Thermostat Housing Kit? Factory coolant routing on LB7 and LLY trucks is restrictive and often interferes with performance modifications. The OEM coolant hose runs across the driver-side valve cover, creating constant clearance issues”especially with upgraded turbos or dual fuel setups. The HSP Thermostat Housing Kit removes these limitations by redesigning the coolant exit path for significantly improved workspace and routing flexibility. What Makes It Different? Unlike the stock unit, the HSP housing reroutes coolant away from the valve cover area, providing room for: Aftermarket and custom turbo systems Dual CP3 fuel pump kits SImplified maintenance access Cleaner, more organized engine bay layouts Each unit is CNC-machined from aluminum and paired with a powder-coated hard tube for exceptional durability and visual appeal. What's Included 1x Aluminum Thermostat Housing (HSP-IN-716-C) 1x Radiator Hose Tube w/ Logo (HSP-IN-229) 1x M8x1.25-25mm Socket Cap Bolt (RFB-909-RFAB) 3x M8x1.25-45mm Socket Cap Bolt (RFB-1032-RFAB) 18" of 3/8" Heater Hose (RFB-395-RFAB) 2x 1/2" Worm Gear Clamp (RFB-405-RFAB) 4x 1-3/4" T-Bolt Clamp (RFB-426-RFAB) 1x 1.75" 90° Rubber Boot (RFB-433-RFAB) 1x 1.75" x 3" Straight Rubber Boot (RFB-437-RFAB) 1x Metric Bonded Seal 14mm (RFB-455-RFAB) 1x M14x1.5 to 3/8" Hose Barb (RFB-692-RFAB) 1x M14x1.5 Port Plug (RFB-969-RFAB) 3x M6x1.0x35mm Flange Bolts (RFB-914-RFAB) 6x M6 Fender Washers (RFB-915-RFAB) 3x M6 Nylon Lock Nut (RFB-916-RFAB) Vehicle Fitment LB7: 2001–2004 (VIN Code 1) LLY: 2004.5–2005 (VIN Code 2) How to Identify VIN Code The engine code is determined by the 8th character of the VIN number. The model year is determined by the 10th character. Overview CNC-machined aluminum thermostat upper housing Creates additional clearance for aftermarket turbochargers Improves access to driver-side fuel system components Includes powder-coated hard tube for a cleaner engine bay Compatible with dual CP3 pump kits Multiple powder coat and custom finish options Ideal for high-power or custom turbocharger configurations Our Warranty HSP NO BS LIMITED LIFETIME WARRANTY At HSP, we believe in our products and stand behind every one that leaves our facility. For years, we’ve gone above and beyond for customers”even without a formal policy. With the HSP “No BS— Limited Lifetime Warranty, that same commitment is now set in stone. We aim to provide clarity, dependability, and support throughout every step of ownership. For more information about our Lifetime, No BS Warranty, click HERE.
HSP One Piece Thermostat Housing Kit for 2001–2005 Chevrolet / GMC Duramax LB7 / LLY The 040-HSP One Piece Thermostat Housing Kit is designed for 2001–2005 Chevrolet and GMC Duramax LB7 and LLY trucks. This forward-facing thermostat housing is a major upgrade for trucks running aftermarket turbos, dual CP3 systems, or custom engine bay layouts. It simplifies coolant routing, increases under-hood clearance, and dramatically improves serviceability and aesthetics. Why Choose the HSP Thermostat Housing Kit? Factory coolant routing on LB7 and LLY trucks is restrictive and often interferes with performance modifications. The OEM coolant hose runs across the driver-side valve cover, creating constant clearance issues”especially with upgraded turbos or dual fuel setups. The HSP Thermostat Housing Kit removes these limitations by redesigning the coolant exit path for significantly improved workspace and routing flexibility. What Makes It Different? Unlike the stock unit, the HSP housing reroutes coolant away from the valve cover area, providing room for: Aftermarket and custom turbo systems Dual CP3 fuel pump kits SImplified maintenance access Cleaner, more organized engine bay layouts Each unit is CNC-machined from aluminum and paired with a powder-coated hard tube for exceptional durability and visual appeal. What's Included 1x Aluminum Thermostat Housing (HSP-IN-716-C) 1x Radiator Hose Tube w/ Logo (HSP-IN-229) 1x M8x1.25-25mm Socket Cap Bolt (RFB-909-RFAB) 3x M8x1.25-45mm Socket Cap Bolt (RFB-1032-RFAB) 18" of 3/8" Heater Hose (RFB-395-RFAB) 2x 1/2" Worm Gear Clamp (RFB-405-RFAB) 4x 1-3/4" T-Bolt Clamp (RFB-426-RFAB) 1x 1.75" 90° Rubber Boot (RFB-433-RFAB) 1x 1.75" x 3" Straight Rubber Boot (RFB-437-RFAB) 1x Metric Bonded Seal 14mm (RFB-455-RFAB) 1x M14x1.5 to 3/8" Hose Barb (RFB-692-RFAB) 1x M14x1.5 Port Plug (RFB-969-RFAB) 3x M6x1.0x35mm Flange Bolts (RFB-914-RFAB) 6x M6 Fender Washers (RFB-915-RFAB) 3x M6 Nylon Lock Nut (RFB-916-RFAB) Vehicle Fitment LB7: 2001–2004 (VIN Code 1) LLY: 2004.5–2005 (VIN Code 2) How to Identify VIN Code The engine code is determined by the 8th character of the VIN number. The model year is determined by the 10th character. Overview CNC-machined aluminum thermostat upper housing Creates additional clearance for aftermarket turbochargers Improves access to driver-side fuel system components Includes powder-coated hard tube for a cleaner engine bay Compatible with dual CP3 pump kits Multiple powder coat and custom finish options Ideal for high-power or custom turbocharger configurations Our Warranty HSP NO BS LIMITED LIFETIME WARRANTY At HSP, we believe in our products and stand behind every one that leaves our facility. For years, we’ve gone above and beyond for customers”even without a formal policy. With the HSP “No BS— Limited Lifetime Warranty, that same commitment is now set in stone. We aim to provide clarity, dependability, and support throughout every step of ownership. For more information about our Lifetime, No BS Warranty, click HERE.
HSP offers a limited lifetime warranty to the original purchaser on eligible HSP products. Underhood powder coating has separate two-year limited coverage. Non-HSP brands follow their own manufacturer warranties. Discontinued products and customer/installer damage are excluded. Claim authorization is required; customer pays inbound shipping for ordinary claims.
Return and warranty information is based on what HSP Diesel offers. Product-specific eligibility and the supplier’s published conditions apply; FullSpecDiesel does not add or extend coverage.
HSP Diesel warranty policyView complete warrantyProduct conditions
Return and warranty information is based on what HSP Diesel offers. Product-specific eligibility and the supplier’s published conditions apply; FullSpecDiesel does not add or extend coverage.
- Return eligibility
- HSP states returns must be postmarked within 30 days of purchase, new and unused with original tags and packaging, with an approved RMA. A 15% restocking fee and customer-paid return shipping apply. Special orders, non-HSP dropship products, apparel, used items and custom colors are excluded. Based on what HSP Diesel offers.
- Return window
- Not stated for this product; see supplier terms
- Restocking fee
- See supplier terms; no product-specific fee stated
- Return shipping
- Based on the supplier’s return policy; see terms
- Made to order
- No
- Backorder status
- Not backordered
- Cancellation
- Subject to supplier terms; contact FullSpecDiesel before requesting cancellation
- Warranty provider
- HSP Diesel
- Warranty duration
- Product-specific duration not stated; see supplier terms
- Compatibility
- Listed for specific vehicle configurations
- Legal use
- Street legal
- Processing estimate
- 3–10 business days supplier processing
- Shipping
- Shipping calculated at checkout
- Signature
- No signature requirement
- Supplier
- HSP Diesel
Product compatibility is based on the vehicle and product information provided. Review your selected truck, product options, measurements, modifications, and installation requirements before ordering.