The 6.6 Duramax is a powerful engine produced by General Motors and Isuzu and has been a great choice for pickups, vans, and medium-duty trucks because of its performance. Although it does perform well, we cannot deny that you are limited in several aspects, not because of the mechanical factors, but of how the engine control unit (ECU) is calibrated by the truck manufacturer. You can do something to maximize its capabilities and improve its drivability and fuel efficiency through appropriate truck tuning methods.
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The Bully Dog 40420 GT Platinum Performance Tuner has impressive and unique software features, which is why it has made it on top of our best diesel tuners for 6.6 Duramax. It is an all-in-one performance booster that does not only increase the horsepower and torque of your truck, it also serves as a monitor to help you assess your driving habits and the potential errors that could hamper your travels. The Bully Dog is compatible with all the Duramax 6.6 trucks from 2001 to 2015. The brand is currently working on a tuner update to match the newer models.
Design and Application
When you purchase the Bully Dog 40420 GT Platinum Performance Tuner, the package comes with the GT head unit, a suction mount, an OBDII Power Distribution block, a DC power connector, an HDMI cord, a USB cable, and a MicroSD card.
The LCD size of this tuner from Bully Dog is 2.4" - just a bit bigger than your dashcam. Most of the buyers have initially thought that it's a touch screen. Unfortunately, it's not. However, navigating is very easy because of the 7 capacitive touch buttons around the main screen. Since these are very sensitive, you don't have to push the buttons just for it to respond.
Before you start the tuning, don't forget to update your device first by attaching the SD card and connecting it to your computer using the USB cord. Go to www.bullydog.com and download the Update Agent. Update it during business hours so in case you have encountered an error, you can immediately call Bully Dog's customer support. A detailed instruction on how to do this is provided on your user manual.
It is preloaded with tunes. Once you have connected it to your OBDII port, the suggested tunes will show on the screen. You can calibrate the parameters based on your preferred performance. The manufacturer suggests you choose the performance or the towing tune.
Why should you purchase it?
The Bully Dog 40420 is known for its Driving Coach. It is an exclusive feature you can take advantage of if you'll bag this highly recommended tuner for your 6.6 Duramax truck. This was designed by the manufacturer to serve as assistance on how you can alter your driving performance to maximize the tuning methods that you have just done. It coaches drivers for better driving habits by providing real-time visual and audio feedback. Remember, regardless of how well you have calibrated the parameters of your vehicle, if you have poor driving habits, you won't be able to fully take advantage of the expected performance.
Another reason why the Bully Dog 40420 on top of our list of the best diesel tuners for 6.6 Duramax is its Safety Defueling feature. After you have downloaded the preferred tuner on your truck, you need to understand that a problem may arise if you fail to responsibly drive it. Adding too much power on a drivetrain that is designed to withstand a certain limit could potentially damage your engine. In order to prevent that from happening, this device has the safety defueling feature that will automatically decrease your power level and will notify you that you have a temperature issue on the screen. The defueling feature is triggered by the boost level or the temperature of your pyrometer, coolant, oil, and transmission. You can calibrate all these so that your Bully Dog performance tuner will know when to go back to its stock tune. Unfortunately, this feature is not available on LML Duramax.
If you want something modern, the Edge 85400 CTS2 Diesel Evolution Programmer is a great choice. It compliments well on all 2001 to 2015 6.6-liter Duramax trucks, from the 2500 chassis to the 5500. Aside from the common features a typical tuner provides, it also allows you to test the different pre-loaded tunes to help you assess which performance will match your day by day road requirements.
Design and Application
The Edge 85400 CTS2 Diesel Evolution Programmer is a modern tuning device that allows you to calibrate the preferred parameters through its full-color, high-resolution touch screen display. It has an ambient light sensor which automatically adjusts the brightness of the screen.
You can mount it on your dashboard or windshield, beside your dashcam, by connecting it to your OBDII through an HDMI cable. The package comes with zip ties so you can secure and hide the cords around your dashboard.
At a glance, this tuner can display 9 parameters at one time. These can be manually set depending on what you want to easily monitor while driving. It can also be used as a display for your Edge backup camera, which you can separately purchase.
Why should you purchase it?
The Edge 85400 CTS2 Diesel Evolution Programmer has 4 pre-set tunes:
- Level 1 - Trans Only: Provides firmer shifts, resulting in longer transmission life.
- Level 2 - Economy: The lowest power level specifically tuned to achieve the maximum fuel economy.
- Level 3 - Towing: Typically used to give you the necessary power if you need to tow heavy loads.
- Level 4 - Performance: The fuel injection and timing are semi-aggressively calibrated to extract the necessary power gains.
- Level 5 - Extreme: The highest power level wherein the fuel injection and timing are aggressively calibrated.
To help you assess which level matches your needs, you can use the Performance Test. You can find it at the right side of your menu, and will help you compare the stock and the chosen level seamlessly. Make sure to only accelerate once the light is green. For the horsepower, ensure that you have appropriately set the right weight of your truck before you start the performance test so that it will give you accurate data.
If you are on a budget yet you are currently searching for the best tuners for diesel 6.6 Duramax, check out the DiabloSport 7203 Predator P2 Performance Tuner. This is packed with features in spite of being the most affordable among the list. It is specifically created for all Sierra or Silverado HD trucks and will boost your Duramax 6.6L engine's horsepower for up to a hundred and increase your miles per gallon by 2 to 4, which is an extraordinary saving if you are a long-haul driver. After the tune-up, you will experience better fuel mileage and additional towing power.
Design and Application
Make sure that your engine is off when you install it and as soon as you get a prompt from the screen that you can start the ignition, just put it on the "on" or "run" position so that you won't get an error message.
As you connect it to your OBDII Port, it will automatically show the quick options where you can change specific parameter to change your factory settings. One example is the tire size. If you have changed your tire to a bigger one, it will also adjust the speedometer limit according to what matches it. As you start tuning, you can choose whether you want an economy for better drivability, towing to help you pull loads or the renowned Diablo tune. What is nice about the device is whenever you choose a tune, it will immediately show you some warning message that you must keep in your mind to ensure that you won't damage your engine after.
The device will save the stock tune before it overwrites the data. This is a great option so that you won't have to visit your car manufacturer for costly reflash.
Why should you purchase it?
Aside from its affordability, the tuning process on the DiabloSport 7203 is quick and easy. Typically, the alterations are done within just 10 minutes. You can also manually adjust the parameters for you to get the maximum performance you'd like your truck to have.
It also clears the Diagnostic Trouble Codes so to fix inexistent errors. If you still see a red warning, seek assistance from an expert truck mechanic.
However, take note that since you cannot mount it on your dashboard, you won't be able to monitor your driving performance. This is a hand-held device that solely calibrates your tune, and should be disconnected after the procedure.
The Hypertech 2100 Max Energy 2.0 Power Programmer is specifically designed for towing purposes. So, if you use your truck to pull loads, here's what exactly you should have. It comes with tunes for most applications, especially for all 6.6L Duramax engine types.
Design and Application
The Hypertech 2100 2.0 Power Programmer has a very basic display - no color nor enticing graphics unlike the first three tuners on the list. However, because of the interface, you can comfortably alter the parameters with its straightforward options.
This device is an application specific tuner that will load parameters based on the allowable calibration for your vehicle. Therefore, just like the others, you are guaranteed that whatever you change will not ruin your truck. You can increase or decrease your RPM with an interval of 100. If you have a teenager who would like to borrow your car, you can even make sure that he won't go beyond 70 MPH just by adjusting the top speed.
Why should you have it?
If you really know how to tune a car, the Hypertech 2100 Max Energy 2.0 Power Programmer is a great tool as it will allow you to set your tunes rather than having to load a pre-calibrated one. This will save you more time instead of waiting for the tune to load and start changing the necessary parameters.
In case you need to bring your car to the manufacturer's shop, you can go back to your stock settings and once you are done, you can flash the pre-set tune that you have set. You don't need to do the manual calibration all over again.
Final Thoughts about the Best Diesel Tuners for 6.6 Duramax
These diesel tuners for 6.6 Duramax will guarantee you that you can increase the performance of your truck. We cannot deny the fact that the 6.6 Duramax is one of the best trucks GM has ever made. However, the opportunity to increase its capabilities should never be taken for granted, especially if you use it on a regular basis. Experience wider torque curve to help you accelerate and maintain your speed by producing more horsepower than being stock with low RPM. If you can drive your truck at a lower rev range, you can achieve better fuel mileage and avoid power loss.
