Fleece Performance Fuel Temperature Sensor Mounting Block For LML Duramax CP3 Conversions - FPE-DMAX-LML-FTSM

The Fleece Performance Fuel Temperature Sensor Mounting Block (FPE-DMAX-LML-FTSM) is a purpose-built solution for anyone performing a CP3 conversion on a 2011–2016 6.6L LML Duramax. When you swap out the factory CP4.2 injection pump for a more reliable CP3, the original mounting location for the return fuel temperature sensor no longer works — this mounting block solves that problem cleanly, keeping your temperature sensor properly secured and your ECM data accurate throughout the conversion.

Key Features & Benefits

• Purpose-designed for LML CP3 conversions: Provides an alternative mounting point specifically engineered for the return fuel temperature sensor when the factory CP4.2 pump location is no longer available after a CP3 swap.
• Maintains proper sensor function: Keeps the return fuel temperature sensor securely mounted so your truck's fuel system monitoring continues to operate correctly — important for tuning, diagnostics, and avoiding fault codes.
• Fleece Performance engineering: Designed by Fleece Performance, a brand with a long track record in Duramax fuel system components including CP3 conversion kits, lift pumps, and injection hardware for the LML platform.
• Diesel-specific component: Built for diesel fuel system applications; not a universal or generic adapter.
• Completes your CP3 conversion properly: Ensures you don't overlook the sensor relocation step, which is a common detail when assembling a full CP3 conversion kit on an LML Duramax.

Specifications

• Brand: Fleece Performance Engineering
• Part Number: FPE-DMAX-LML-FTSM
• Fuel Type: Diesel
• Application: Return fuel temperature sensor mounting for LML Duramax CP3 conversions
• CARB Status: Not CARB legal; not for sale in California

Fitment

This fuel temperature sensor mounting block fits:

• 2011–2016 Chevrolet Silverado 2500HD / 3500HD with 6.6L LML Duramax diesel
• 2011–2016 GMC Sierra 2500HD / 3500HD with 6.6L LML Duramax diesel

Important: This part is intended for use when performing a CP3 injection pump conversion on the LML Duramax. It is not designed for trucks still running the factory CP4.2 pump. It does not apply to earlier Duramax generations (LB7, LLY, LBZ, LMM) or later generations (L5P), as those use different fuel system configurations.

Why Buy from ThreePiece.us

ThreePiece.us offers free shipping on every order — no minimums, no catches. If you have questions about whether this sensor mounting block is the right piece for your specific CP3 conversion build, our team is here to help; reach out via the fitment help contact on the product page or call us directly. Need to spread out the cost of your build? Financing is available through Affirm, so you can get your Duramax conversion parts now and pay over time. With over 10,000 customers served and expert product support, ThreePiece.us is a trusted source for performance diesel parts.

Frequently Asked Questions

Q: Why do I need this mounting block when doing a CP3 conversion on my LML Duramax?
A: The LML Duramax uses a return fuel temperature sensor that, on the factory setup, is mounted in a location associated with the CP4.2 pump. When you convert to a CP3, that mounting location is no longer usable. Fleece's FPE-DMAX-LML-FTSM provides an alternative method to mount and secure the return fuel temperature sensor so it remains properly positioned in the fuel system.

Q: Will this work with any LML CP3 conversion kit, or only Fleece's?
A: The part is designed and sold by Fleece Performance specifically in the context of LML CP3 conversions. Fleece offers several LML CP3 conversion kits (such as FPE-LML-CP3-WP, FPE-LML-CP3-NP, and FPE-LML-CP3-10). If you're unsure whether this block is compatible with a third-party conversion kit you're using, contact our team for fitment guidance before ordering.

Q: Does this fit the 2017 and newer L5P Duramax?
A: No. This part is specifically for the 2011–2016 6.6L LML Duramax. The L5P (2017+) uses a different engine and fuel system architecture and is not supported by this component.

Q: Can I purchase this product if I live in California?
A: No — this product is not CARB legal and is not for sale in California.