Best CP3 Conversion Kit for LML Trucks

I’ve spent countless hours researching and, let’s be honest, wrenching on my own LML Duramax. The stock CP4 fuel pump? A constant source of anxiety. That’s why I dove deep into finding the best CP3 conversion kit. This guide is the result – a comparison of top options to help you make the right choice for your truck. You’ll find detailed reviews, practical comparisons, and answers to the most frequently asked questions. Let’s get started!

IMAGE	PRODUCT NAME	AMAZON LINK
	Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…	View on Amazon
	Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…	View on Amazon
	BIGREAT CP4 to CP3 Fuel Injection Pump Upgrade Conversion…	View on Amazon
	Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…	View on Amazon
	Fleece Performance Engineering -LML-CP3-FF-10 2011-2013 Lml…	View on Amazon
	S&S Diesel Motorsport® 50 State LML CP3 Conversion…	View on Amazon
	LML CP3 Conversion Kit without Pump Replacement for Chevy…	View on Amazon

Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…

Fleece Performance is a name synonymous with Duramax reliability. Their CP3 conversion kits are known for their quality and ease of installation. This kit provides a straightforward upgrade path, boosting fuel delivery and eliminating the weak link of the factory CP4.

• Replacement Parts
• Made from quality materials
• Designed to fit your vehicle
• Injection Pumps & Controllers
• FPE CP3 Kits

Pros:
– Excellent reputation
– Relatively easy installation (depending on experience)
– Significant improvement in fuel system reliability

Cons:
– Can be pricey compared to other options
– Some users report minor fitment issues (rare)

User Feedback Summary: Mostly positive reviews praising the quality and performance increase. A few minor complaints about installation complexity, but nothing major.

Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…

This is likely another variation of Fleece Performance’s kit, possibly differing in included components or specific part numbers. Without knowing the exact differences from the first listed Fleece kit, I’d recommend checking the Amazon listing for specifics.

• Replacement Parts
• Made from quality materials
• Designed to fit your vehicle
• Injection Pumps & Controllers
• FPE CP3 Kits

Pros:
– Likely shares the same positive qualities as the first Fleece kit
– Reputable brand

Cons:
– Price could be a factor
– Requires confirming the specific differences compared to other Fleece options

BIGREAT CP4 to CP3 Fuel Injection Pump Upgrade Conversion…

The BIGREAT kit offers a more budget-friendly alternative. While it lacks the name recognition of Fleece, it promises a reliable upgrade to the CP3 system. Always double-check compatibility with your specific LML year and model.

• Application: Compatible with 2011-2016 Chevy Silverado 2500/3500 HD 6.6L Duramax Diesel
• Application: Compatible with 2011-2016 GMC Sierra 2500/3500 HD 6.6L Duramax Diesel
• Function: Upgrades to the more reliable CP3 system
• Materials: High-quality materials, durable, corrosion-resistant
• Package Includes: 1x Upgraded Performance CP4 to CP3 Conversion Kit

Pros:
– More affordable option
– Straightforward upgrade

Cons:
– Less established brand, so long-term reliability might be a question mark for some.
– Potentially less robust components compared to premium brands

User Feedback Summary: Limited reviews available compared to Fleece. More research on specific user experiences is recommended.

Fleece Performance – 11-16 GM 2500/3500 Duramax LML CP3…

This is another Fleece Performance listing. Check the specifics to identify any key differences from the first two Fleece listings. The variations in their offerings might relate to specific component differences or bundled parts.

• Replacement Parts
• Made from quality materials
• Designed to fit your vehicle
• Injection Pumps & Controllers
• FPE CP3 Kits

Pros:
– Quality and reliability associated with Fleece
– Improved fuel system performance

Cons:
– Price point
– Need to verify specific differences between this and other Fleece kits

Fleece Performance Engineering -LML-CP3-FF-10 2011-2013 Lml…

This Fleece Performance kit highlights its focus on the 2011-2013 LML models. The part number is crucial; ensure it’s compatible with your specific truck year and engine.

• Item Package Dimension: 16.0L x 16.0W x 12.0H inches
• Item Package Weight – 25.0 Pounds
• Item Package Quantity – 1
• Product Type – AUTO PART

Pros:
– Fleece Performance quality
– Specifically designed for earlier LML years

Cons:
– May not be suitable for all LML years (2014-2016)
– Price point

S&S Diesel Motorsport® 50 State LML CP3 Conversion…

S&S Diesel Motorsport offers a 50-state legal option. This is a significant advantage if emissions compliance is a priority.

• More durable plug-and-play replacement for the CP4
• Does not require ECU calibration
• OE fit and function
• 50 State Legal / CARB Compliant (EO# D-756-4)
• Two-year, unlimited-mile warranty

Pros:
– Emissions compliance
– No ECU tuning required
– Warranty included

Cons:
– May be slightly more expensive
– Check for compatibility with your specific year

LML CP3 Conversion Kit without Pump Replacement for Chevy…

This kit stands out as it doesn’t include the pump itself. This option could be beneficial if you’re already sourcing a CP3 pump separately or have one on hand.

• Interchange Part Number: FPE-LML-CP3-NP, DD-LMLCP3
• Replacement for Chevy Silverado 2500 HD Durumax Diesel 2011-2016
• Replacement for Chevy Silverado 3500 HD Durumax Diesel 2011-2016
• Replacement for GMC Sierra 2500 HD Durumax Diesel 2011-2016
• Replacement for GMC Sierra 3500 HD Durumax Diesel 2011-2016

Pros:
– Cost savings if you already have a pump
– May be a good option for those comfortable sourcing individual parts

Cons:
– Requires sourcing a separate CP3 pump
– Installation might be more involved

Practical Buying Advice:

Your choice depends on your budget and mechanical skills. Fleece Performance consistently receives high marks for quality and reliability, but they command a premium. BIGREAT and other budget options might be suitable for mechanically inclined users comfortable with potential compromises. Consider the warranty and emissions compliance when making your decision. Always verify compatibility with your specific LML model before purchasing.

FAQ:

Q: Will a CP3 conversion void my warranty? A: It likely will void your factory warranty. Check with your dealer before proceeding.

Q: Do I need tuning after a CP3 conversion? A: Some kits require tuning, while others are designed to work without it. Check the product specifications.

Q: How difficult is the installation? A: It’s a moderately involved job requiring mechanical skills. Some kits are easier to install than others.

Q: How much does a CP3 conversion kit cost? A: Prices vary widely depending on brand and kit components, from several hundred to over a thousand dollars.

Q: What are the long-term benefits? A: Increased reliability, improved fuel delivery, and potentially increased power are key long-term benefits.

Q: What are the potential risks of a CP3 conversion? A: Incorrect installation can lead to fuel system problems. Choosing a reputable kit and installer is crucial to minimizing risk.

Remember, this is a guide. Always double-check compatibility and consult with a qualified mechanic if you’re not comfortable with the installation yourself. Happy wrenching!