Modified CP3K

Features:

• Eliminates fuel flow restriction at 3000 RPM
• Maintains fuel rail pressure across RPM range
• Improves horsepower at higher engine speeds
• Modified for performance over stock CP3
• Designed for 2001–2016 Duramax 6.6L engines
• Direct replacement for factory CP3 pump
• Ideal for tuned and high-demand applications
• Retains factory fitment and drivability
• Cost-effective alternative to full CP3 conversion
• Supports consistent fuel delivery under load
• Perfect for daily drivers and mild race setups
• Requires regulator scaling on LB7 and LLY models

Get More Power When Your Duramax Needs It Most

If you're pushing your Duramax hard and want more power where it really counts, the Fleece CP3K is a no-brainer upgrade. Your stock CP3 pump starts falling short after 3000 RPM, choking off fuel flow and killing performance right when your engine needs it most. The CP3K solves that issue by eliminating the factory restriction, giving you smooth, consistent fuel delivery all the way through the powerband. That means no more dropping rail pressure under load, no more missed opportunities for power, and no more compromises when you're towing, racing, or daily driving. This is the kind of upgrade that makes your truck feel alive again, especially if you're tuned or running other supporting mods. You’re not just buying a part, you’re unlocking the potential that was always there. And since it’s a direct replacement, it keeps things simple without the need for crazy fabrication or custom tuning beyond what’s already expected.

Built To Maintain Fuel Flow Beyond 3000 RPM

The Fleece FPE-DMAX-CP3K is a performance-modified CP3 pump based on the factory LBZ design and engineered specifically for Duramax 6.6L engines from 2001 to 2016. It addresses the stock pump’s biggest flaw, its inability to maintain adequate fuel flow past 3000 RPM, by increasing internal efficiency and flow capacity. This results in a much more stable fuel rail pressure curve, even under high-load or high-RPM scenarios, making it ideal for tuned trucks, towing applications, or light competition use. It bolts in place of your existing CP3 without changing your fuel system layout, keeping installation straightforward and dependable. The pump supports high-performance builds without going all-in on a dual CP3 or CP4 conversion, offering a smart balance between cost and capability. For LB7 and LLY trucks from 2001 to 2005, scaling the fuel pressure regulator properly will be necessary to ensure ideal performance. Whether you’re trying to fix a weak spot or build a more capable setup, this pump delivers consistent results under pressure.

Fits: 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax

Notes:

• Eliminates fuel flow restriction at 3000 RPM
• Designed to maintain rail pressure at high RPM
• Ideal for tuned or performance Duramax engines
• Direct replacement for factory CP3 pump
• Compatible with 2001–2016 6.6L Duramax engines
• Uses factory fuel system layout and connections
• Fuel pressure regulator must be scaled for 2001–2005 LB7 and LLY models
• Not a dual CP3 or CP4 conversion kit
• Supports high-load and towing applications
• Cost-effective upgrade compared to full fuel system replacements
• Professional installation and tuning recommended for optimal results