Best Diesel Tuner for 6.6 Duramax – 2020 Update LB7-L5P

Vehicle enthusiasts think of the engine as the heart of the vehicle; Interestingly enough, the 6.6 Duramax is shaped like a heart!

DMAX produces a family of 6.6L diesel engines named Duramax, a collaboration between General Motors and Isuzu, a Japanese diesel engine production company. 

Tune manufacturers are catering to (or working around) emissions regulations to create the best tuners possible. The possibilities are incredible even while keeping trucks emissions-compliant - these are truly the best programmers for Duramax trucks!

Our Top Picks for Diesel Tuners for 6.6 Duramax

  • Forced Regens
  • Warranty Friendly
  • SOTF Capable
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  • Cloud Tune Delivery
  • Lifetime Custom Tune Support
  • Uses Phone/Tablet for Display
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  • 5" HD Touchscreen
  • Quick Startup
  • Preloaded Tow/Performance Tunes
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Comparison of the Best Diesel Tuners For 6.6 Duramax

  • Doesn't flash your ECM/TCM avoiding Warranty hassles
  • ActiveSafety & TransCommand features ensure longevity and safety
  • 5 Power Levels plus a Stock power level
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  • Price includes lifetime custom tune support from GDP Tuning
  • Easy Flashing via OBDII port gets you on the road in minutes
  • App provides 1on1 chat with your tuning technician
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  • Preloaded tunes plus the best PID monitor/gauge setup on the market
  • 5" customizable touchscreen with endless gauge layout possibilities
  • Includes a windshield mount for easy viewing/storage
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  • Allows for speed/rev limiter removal
  • 3-4 Preloaded Tunes depending on year
  • Tire Size Changes for Speedo Corrections
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  • Retrieves more PIDs than most tuners/monitors
  • Improved internal hardware for instant repsonsiveness
  • Can be run alongside any tuner for monitoring PIDs
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What Should I Look For When Buying a Tuner For a 6.6 Duramax?

The Right Tune For You

There are many different tuners on the market, but the tune itself determines how well your truck is going to run, as well as how much power you're going to gain. Tuners with preset tunes are great in terms of performance, extensively tested, and cost-effective.

However, custom-made tunes are catered to your exact needs; Offroading, improving fuel economy, or squeezing the last drop of power from your Duramax are all possible with customized tunes.

Banks Derringer

Warranty Friendly Tuners

Warranty friendly tuners allow you to reap the benefits of tuning your truck while still keeping it in warranty. Trucks can malfunction from time to time, and even though Duramax is a reliable platform, having a warranty on it will save you money and headaches. That's why tuners that leave no traces in the ECU are sought after. However, if you have a great connection with a dealership and have a tuner that doesn’t warranty friendly, they might still work on your truck.

Tracking Parameters (PIDs)

Monitors and gauges are immensely helpful, ensuring your truck is running as intended, as well as being aware of any issues that might come up, especially after tuning. Parameter tracking is the reason tuners with monitors included are more sought after. That way you can monitor your EGTs, boost, IAT, and others.

Quick Take - Best Tuners for the 6.6 Duramax

Before you get too far, here are the three best tuners for the 6.6 Duramax: 

  1. Banks Derringer
  2. EZLynk Tuner with GDP Tunes
  3. Edge Evolution CTS2

Review of the Best Tuners for the 6.6 Duramax

These tuners are the best on the market for each model of the 6.6 Duramax.

Best for L5P Tuning Duramax:
Banks Derringer


  • The tuner works even in cruise control
  • Warranty friendly tuner that requires no reflash
  • Simple updates through iDash with a microSD card
  • Banks Derringer allows for forced regen of your truck
  • Health monitor that returns the truck to stuck in case of any malfunctions


  • Since the Derringer doesn’t flash the ECU, it can’t remove the speed limiter
  • Banks Derringer is an inline tuner making the installation more involved than an OBDII flash

What Other 6.6L Duramax Owners are Saying

Customers have reported a noticeable increase in power, but note that it's not AS much as some others claim. The gauge monitors everything necessary, and the shift-on-the-fly ability is great. The tuner is warranty friendly, so the Banks Derringer is the perfect tuner if you want to keep your truck in warranty. Highly recommended by L5P 6.6 Duramax owners.

Why it Stands Out to Us

The Banks Derringer has six different power levels with torque and horsepower well distributed across the rpm range, from idle to shift point. The 6th level offers the most power, and it's the optimal level for performance, while the 3rd level offers a comfortable driving experience and is ideal for towing.

The iDash monitor provides the driver with parameter information, performance testing, and the ability to diagnose issues. The health monitor and the ActiveSafety feature work to protect your truck, transitioning it to stock power and bypassing the tuner in case any issues arise. TransCommand modulates the power to improve shift performance and increase the longevity of the transmission.

Bottom Line

The Derringer is an excellent tuner for the L5P 6.6 Duramax. The device will make you wish you tuned your truck sooner. With its many features and warranty friendliness, you can enjoy the performance enhancements without any drawbacks!

Best Custom Tuner for LML Tuning:
EZLynk Tuner w/ GDP Tunes


  • Lifetime of custom tunes from GDP
  • Automatic updates through the AutoAgent app
  • True cloud-based tuning will make your life easier
  • Tracks most parameters
  • Ease of use thanks to the AutoAgent App


  • Doesn't come with a monitor included; instead, you have to use a smartphone or tablet (or an Insight CTS3 works great if you have one)

What Other 6.6L Duramax Owners are Saying

The custom tunes from GDP are excellent, many Duramax owners on the forums claim they're one of the best diesel tuners out there. The installation and use of the EZLynk AutoAgent 2 are as simple as can be. The device plugs right into the OBDII Port. To use the tuner, you only need a phone; the tunes are easy to load, and the updates are automatic.

Why it Stands Out to Us

EZLynk AutoAgent 2 comes with lifetime support from GDP, and Nick there is highly praised for his magic with diesel powerplants. They will provide you with as many custom tunes as you'd like; tunes that will unlock the full potential of your LML 6.6 Duramax!

The tuner can monitor many different parameters with the customizable gauge screens. Reaching technical support and exchanging information has never been simpler thanks to the cloud-based tuning and instant messaging. 

The smartphone app provides some excellent digital gauges, and if you don’t want to use your personal phone a cheap tablet/spare phone works great. The app also lets the user scan and clear diagnostic codes like most tuners do.

Bottom Line

Custom tunes from GDP are the way to go if you want to experience the full potential of the 6.6 Duramax. The tuner's usability is on the next level, coming with every necessary feature provided through the smartphone app. All in all, an excellent choice!

Best Duramax Tuner with Display:
Edge Evolution CTS2


  • Multiple preset tunes with their own purpose
  • Diagnostic tool allows you to read and clear codes
  • Excellent monitor with a lot of customization possibilities
  • Performance testing feature provides real-world 0-60 times and more
  • Maintenance manager that reminds you when the maintenance is due


  • Extreme tune isn't available for 2011 to 2016 model years
  • The tuner isn't compatible with LB7 or LLY trucks with manual transmissions

What Other 6.6L Duramax Owners are Saying

The Edge Evolution CTS 2 offers moderate power gains at each power level. Some customers have reported an improvement in mileage, while others claim that the mileage stayed the same. The monitor is flawless, so much so that many purchase the tuner for the monitor only (although we recommend the Insight model for this). The tuner has many excellent features, the lack of the SOTF feature being the only complaint.

Why it Stands Out to Us

The Evolution CTS2 is an all-around excellent tuner. The five different power levels offer an option for every condition; transmission only, economy, towing, performance, and extreme. Each level is adjustable in a user-friendly way, with the possibility of restoring the truck to factory settings.

The tuner connects with one cable to the OBDII port, resulting in a clean look. The highly customizable monitor looks pristine, monitoring, and displaying vital data in real-time. Track your truck's performance with the data logging feature, or test the tune for real-life scenarios with the performance testing feature.

Bottom Line

Superb all-around tuner with five different preset tunes and a clean, easy to navigate monitor will make you fall in love with your truck all over again! Take the next step, and drive your Duramax the way it's supposed to be driven.

Best Budget Duramax Tuner:
Diablosport Predator


  • Great performance improvements considering the price
  • High-resolution screen with simple five-button navigation
  • Unmarrying' the device is as simple as contacting DiabloSport
  • Predator 2 allows adjustments for tire size, removing the top speed limiter, shifting, and more


  • The tuner lacks in the monitoring department
  • Top speed can't be raised without disabling cruise control

What Other 6.6L Duramax Owners are Saying

DiabloSport Predator 2 does everything it should and more for a low price. Each one of the four tunes does exactly what it was made to do, next to making driving a better experience. The performance tune makes the truck accelerate like a beast. The towing tune will let you tow anything you need to haul. Some customers have noticed an improved fuel economy, while others claim that the mileage stayed the same.

Why it Stands Out to Us

The DiabloSport Predator 2 fits Duramax models from 2001 to 2015, offering up to 135 horsepower and 240 pounds of torque - (Diablosport claim). That in itself is worth the price tag.

The tuner comes with four different preset tunes: towing, economy, performance, and extreme, as well as the option for adjusting transmission shift firmness and shift points that many are after.

Simple plug and play installation and easy navigation through the screen make for an effortless experience. Lacking in fancy features, the tuner has only the essentials, such as the diagnostic and the data logging feature.

Bottom Line

This little device will turn your 6.6 Duramax into a monster at an incredibly low price! Adjust the truck by reprogramming gear ratio, removing the top speed limiter, and making it your own.

Best Monitor-Only Option:
Edge Insight CTS3


  • Simple installation resulting in a clean look
  • The device works with every model of the Duramax
  • Switch between economy, towing, and performance tracking
  • Ability to track and test performance of the vehicle as well as the driver
  • The Edge Insight CTS3 tracks parameters and displays information in real-time


  • Over-exposure to the sun can damage the monitor
  • Some users have reported buggy behavior but complaints are inconsistent

What Other 6.6L Duramax Owners are Saying

Duramax (and all diesel enthusiasts) agree that the Edge Insight CTS3 is a magnificent addition to every truck. The monitor looks clean, without the tacky cables, and the updates for the software don't require a PC. The customization possibilities are endless, resulting in a stylish look. With this device, you can track even the most uncommon parameters.

Why it Stands Out to Us

Track and observe the parameters of your truck with the elegant monitor that is the Edge Insight CTS3. The display is an unmatched stand-alone monitor, furthermore, some custom tuners are able to work with it to operate their SOTF. The installation with the OBDII port is simple, without required wiring. The software itself is Wi-Fi updatable.

The Insight CTS3 offers a vast choice of customization options for the layout, gauges, and backgrounds. Next to monitoring vital engine parameters, the monitor also measures performance such as 1/4 mile and 0-60 time. To round out the device, Insight CTS3 has a data logging feature as well as the ability to read and clear DTC codes.

Bottom Line

The perfect addition for enthusiasts who want to monitor the truck's performance without programming or those that have made tremendous upgrades and just want to monitor the vehicle for ensured safety. The Edge Insight CTS3 makes driving a pleasure.

Types of Tuners for the 6.6L Duramax

Let's quickly recap the types of tuners that are not on the market, what they mean, and what you can expect:

"Canned" Tuners

"Canned tunes" are developed for a specific model engine; However, as is the case with Duramax, they can be developed for multiple models of the same engine. Because they aren't created for your application exactly, they won't get the most power possible out of your truck.

Canned tunes are made for stock vehicles, and they cannot benefit from aftermarket enhancing modifications. These types of tunes are created after extensive testing on a stock vehicle. They are cost-effective since they are mass-produced and sold.

The Banks Derringer, the Edge Evolution CTS2, and the DiabloSport Predator 2 we reviewed here are excellent canned tuners for the Duramax

"Canned" Tuners with Custom Tune Abilities 

"Canned tunes" with custom tune abilities have preset tunes from the manufacturer, and they can load custom tunes made from 3rd parties. The canned tunes are great, but if you want the truck to run the best it can, custom tunes are the way to go.

Custom tunes are developed specifically for your truck, and these tunes take into account the modifications you have made or plan on making. Custom tunes can be created by notifying the tune manufacturer of your setup and receiving a tune or taking the truck to a tune shop to get tested and tweaked until perfection. 

The Diablosport Predator 2 does come in a “Platinum” version that accepts custom tunes, but that is not the version we reviewed here.

Custom Tuning Modules

Custom tuning modules are used in high-performance applications since they can push the vehicle to its limits. For a custom tuning module, you will need to purchase a custom tune made from an outside source; preferably a shop/tuner with a well-known brand name. Such as GDP Tuning, which the AutoAgent reviewed above includes!

Generally these tuners still connect via OBD-II and flash the ECM/TCM, as normal canned tuners do (at least these days). The real difference here is your tuning technician can factor in the fact you have a built transmission, larger injectors, or a turbo large enough to stick your head in - squeezing every ounce of capability out of your mods.

The EZLynk Tuner reviewed here falls under this category.

Cautious Considerations to Keep in Mind

The Tune for Your Model Engine

Duramax is a family of engines made from 2001 to current, and most tuners are created for a specific make/model/year engine. It's important to purchase a tuner that is compatible with your exact model.

Edge Evolution CTS2

Duramax RPM Limit

Tuners most usually increase the rev limit, opening Duramax up to more performance potential, and in turn, increasing horsepower and torque. Completely stock Duramax will operate normally up to 4,000 RPM; Anything higher than that and the engine can become susceptible to damage. 

It's best to follow the instructions from the tune manufacturer in order not to damage the truck. Duramax engines are diesel, and diesel engines don't need to rev high! Your chances of damaging something increase dramatically over the OEM rev limiter.

Diesel Particulate Filter (DPF)

Duramax engines from 2007.5 model years require a diesel particulate filter. The DPF filter does hold the truck back in terms of performance, power, and fuel economy. Deleting the DPF filter in performance applications isn't uncommon. However, removing emissions control devices is illegal, and it's possible to reach extraordinary performance numbers even with the diesel particulate filter intact.


An engine shaped like a heart with great performance potential deserves the right upgrades. And a truck needs to be powerful, robust, menacing. These tuners are the perfect upgrade for the Duramax powerplant, and they will turn your truck into a berserker.