Top 9 Diesel Tuners for 6.6L Duramax in 2022

When it comes to Duramax engines, “firmware” or “chip tuning” includes 3 completely different phenomena – programmers, chips to be installed in the wiring harness and custom firmware using EFI Live / HP tuners. Let’s consider the pros and cons of these solutions.

Programmers are devices that contain a set of ready-made firmware for the engine control module/unit – ECM/ECU, capable of writing this firmware via the diagnostic connector OBD-II port, the one on the driver’s side under the dash.

Usually, programmers allow you to adjust the size of tires, gear ratio, speed limiters, read and clear diagnostic trouble codes (DTC), etc. In some cases, a few diagnostic functions are also added – nozzle adjustments, fuel pressure corrections, etc. Such devices are mainly required for firmware, performance boost, or diagnostics. Often, a programmer saves your stock firmware, allowing you to get back to it when you want.

Edge, PPE, Bully Dog, Hypertech are all programmer manufacturers. The first one is quite a compromise if you need extended diagnostic functions along with increased dynamics and reduced fuel consumption, the last one is for those who want to minimize the risk of breakages; Hypertech’s firmware is quite conservative.

Programmer abilities

  • Slightly increased horsepower, torque, mileage, fuel economy, and overall vehicle’s performance;
  • Firmware modifications or getting back to stock settings in 5 minutes;
  • Adjusting of wheel sizes, speedometers, gear ratio, transmission, cooling fan, rev and speed limiters, reads and clears DTCs, data logging, and diagnostics, monitors/records real-time stats and parameters, storing multiple custom tunes, etc.;
  • Firmware updates via an Internet connection.

Be careful with the speed limiter. Transmission ratio and a category of tires are not the limits when it comes to these devices.

Below we have a list of the best tuners/programmers for 6.6L Duramax. Help yourself and choose your perfect fit!

Tuners for GM 6.6 Duramax – Comparison Chart

Bully-Dog-40420 Bully Dog 404202.5” dynamic LCDClears/reads DTCsView on Amazon
Edge Products 85400 Edge Products 854005″ full-color HR touchscreenMonitoring of engine parametersView on Amazon
DiabloSport 8245 DiabloSport 8245full-color touchscreenClears/reads DTCsView on Amazon
Superchips 2845DiabloSport 7202full-color 2.8″ HD screenClears/reads DTCs, in real-timeView on Amazon
Hypertech 32501 Hypertech 32501monochromeClears/reads DTCsView on Amazon
SCT Performance 40490 SCT Performance 40490full-colorClears/reads DTCsView on Amazon
HP Tuners MPVI2 M02-000-02 HP Tuners MPVI2 M02-000-02NoClears/reads DTCsView on Amazon
PPE 111010000 PPE 111010000monochromeClears/reads DTCs, in real timeView on Amazon
Banks 66411DiabloSport 8200full-color 2.8″ screenClears/reads DTCsView on Amazon

Best Diesel Tuners for 6.6 Duramax Engine

Bully Dog 40420 – Best Diesel Tuner for 6.6 Duramax

Bully Dog 40420

The Bully Dog 40420 is a GT Diesel tuner able to fully provide greater HP, torque, and better fuel economy for your truck and make your 6.6L Cummins work more efficiently. With this versatile smart tuner, you will satisfy the most unique demands you have for your vehicle. This device is really easy to operate, so you will have absolutely no problems with monitoring over 15 performance parameters.

This device can read and clear your diagnostic trouble codes as well and provide a truly smooth engine operation. The kit includes everything necessary for proper operation and convenience, including a 2.5” dynamic LCD display, customizable gauges, and a windshield mount to have all the readings right in front of your eyes. The tuner is also dyno-proven and can store up to 10 custom tune files to match various needs and get the best from your vehicle. You can also get free Internet updates.


  • Model – 40420
  • Weight – 2 lbs
  • Dimensions – 2.25″ x 3.5″
  • All instructions and hardware included (OBDII adapter plug, windshield mount, SD card reader, SD card, mini USB cable, power cable, fuse tap, fuse spade).

Vehicle fitment

  • 2001-2015 Chevy/GMC 2500/3500HD 6.6L Duramax
  • 2006-2010 GM Kodiac/Topkick 4500/5500 6.6L Duramax
  • 2006-2014 GM Savannah/Express 2500/3500 6.6L Duramax
  • 1999-2015 Ford F-250 to F-550 Super Duty & Excursion 6.0/6.4/6.7/7.3L Powerstroke
  • 2003-2015 Dodge & Ram 2500-5500 5.9L/6.7L Cummins
  • 199-2005 Ford Excursion 7.3L/6.0L Powerstroke


  • Improves horsepower, fuel economy, and torque
  • Multiple parameters monitoring (over 15 performance parameters)
  • Clears/read DTCs for proper engine operation
  • The large dynamic LCD display
  • Dyno proven performance
  • Stores up to 10 custom tune files
  • Free Internet updates
  • Easy operation

Edge Products 85400 Diesel Tuner for 6.6 Duramax

Edge Products 85400

This powerful and easy-to-use programmer will easily re-program the stock board computer of your vehicle by uploading the Edge calibrations to provide improved performance. You can expect up to 180 HP and 440 lb-ft on diesel trucks! This device features various custom-tuned power levels to increase horsepower, torque, MPGs, and the overall performance of your vehicle.

The user-friendly single-touch menu navigation of this programmer allows you to take full control of your vehicle, whether it’s shift points/firmness, TQ management, or fuel pressure tuning.

The 5″ full-color HR touchscreen with a sleek casing design is pleasing to the eye, and you will feel that once you install the device. The Evolution has various diagnostic features to choose from, as well as customizable backgrounds and multiple gauge screen layouts. You can make speedometer adjustments, adjust speed and rev limiters, and monitor the real-time performance of your vehicle. Not legal in California.


  • Model – 85400
  • Dimensions – 9.5” x 6.5” x 3.7”
  • Weight – 1.7 lbs
  • All instructions and hardware included

Vehicle fitment

  • Chevrolet Silverado 2500 2001-2015 6.6L Duramax
  • Chevrolet Silverado 3500 2001-2015 6.6L Duramax
  • Chevrolet Silverado 4500 2001-2013 6.6L Duramax
  • Chevrolet Silverado 5500 2001-2013 6.6L Duramax
  • GMC Sierra 2500 2001-2015 6.6L Duramax
  • GMC Sierra 3500 2001-2015 6.6L Duramax
  • GMC Sierra 4500 2001-2015 6.6L Duramax
  • GMC Sierra 5500 2001-2015 6.6L Duramax
  • Dodge/Ram 2500 2003-2012 5.9L and 6.7L Cummins
  • Dodge/Ram 3500 2003-2012 5.9L and 6.7L Cummins
  • Ford F-250 1994.5-2003 7.3L, 2003-2007 6.0L, 2008-2010 6.4L, 2011-2015 6.7L
  • Ford F-350 1994.5-2003 7.3L, 2003-2007 6.0L, 2008-2010 6.4L, 2011-2015 6.7L
  • Ford F-450 2008-2010 6.4L, 2011-2015 6.7L
  • Ford F-550 2008-2010 6.4L, 2011-2015 6.7L
  • Ford Excursion 2000-2003 7.3L, 2003-2005 6.0L


  • Enhanced mileage, towing, and overall performance
  • Diagnostic features
  • User-friendly interface
  • Real-time performance monitoring
  • Improved MPGs
  • Sleek casing design
  • 5″ full-color HR touchscreen
  • Easy menu navigation
  • Up to 180 HP and 440 lb-ft on diesel
  • Speedometer adjustments
  • Speed and rev limiters adjustments
  • Multiple gauge screen layouts
  • Customizable backgrounds
  • Internet updatable
  • Easy to install

DiabloSport 8245 Diesel Tuner for 6.6 Duramax

DiabloSport 8245

The DiabloSport 8245 inTune i3 Platinum Performance Programmer is ready to scan your vehicle and wake up your 6.6L Duramax taking its horsepower and torque to another level and providing versatile modifications and adjustment capabilities.

You don’t have to get any other tools, just use this smart programmer to eliminate any transmission, AFM, or drivetrain issues, or enhance your truck’s power abilities, no matter what aftermarket part has been added. When it comes to DiabloSports, you are only limited to your imagination.

This device will make your modifications truly work for your vehicle to stand out on the road. You can expect perfect tuning for various aftermarket modifications! The 8245 comes pre-loaded with different custom tunes, thoughtfully created by engineering experts at DiabloSports.

You can choose between data logging, idle RPM, improved MPGs and throttle response, better drivability, top speed/rev limiters, speedometer calibrations Cooling, DTC reading/clearing, and even fan control – or you can have it all! The device is incredibly user-friendly and doesn’t cost that much at all.

Will not work on Hybrid or E-Assist vehicles. Designed to be used with Premium fuel. This is a Race Only product that is to be used solely for competition on Racing Vehicles.


  • Model – 8245
  • Dimensions – 6.1″ x 5.4″ x 2.4″
  • Weight – 1.6 lbs
  • All hardware included

Vehicle fitment

  • GMC
  • Canyon 2008-2012, 2015-2016
  • Sierra 1500 1999-2016
  • Sierra 2500 1999-2006, 2008, 2014-2016
  • Sierra 3500 2001-2006, 2008, 2014-2016
  • Yukon 2000-2012, 2014-2016
  • Yukon Denali 2005-2015


  • Improved horsepower and torque
  • Multiple pre-loaded tunes
  • Data logging
  • Cooling fan control
  • Idle RPM
  • Improved MPGs
  • Improved throttle response
  • Better drivability
  • Top speed / rev limiter
  • Speedometer calibrations
  • User-friendly navigation
  • Clears and checks DTCs
  • Perfect tuning for various aftermarket modifications
  • Affordable price

DiabloSport 7202 Diesel Tuner for 6.6 Duramax

DiabloSport 7202

Are you ready for a whole new driving experience? The Diablosport 7202 tuner can make you fall in love with your truck all over again as you’ve just bought it!

All you have to do is plug the device in your OBD-II port via the supplied cable connected to the tuner, choose any of the available features, and witness how smooth your truck’s performance gets! Various modes, pre-loaded custom tunes, and adjustments are here for you to try and find the perfect one that suits your needs.

Diablosport predictors will get you ready for the ideal performance upgrade for your GM truck. It does not matter the GM model of the car you have. It will ramp up your performance in such a big way.

It is loaded with programs for 4.3L, 4.8L, 5.3L,6.0L, AND 8.1L GM trucks and the USV from 1999-2017.

You can gain power up to 25 horsepower and 25 ft/lbs of torque without popping the hood while running the predator’s performance.

The predator increases your truck’s performance and avails flexible options like programming the tires, gear ration, and removal of the top speed limiter. It’s a long-lasting legend predator due to its simple plug-and-play installation.


  • Manufacturer: Diablosport
  • Weight: 1.19 pounds
  • Model number 7202
  • Dimensions: 5*6*2.5 inches

Vehicle fitment

  • It is compatible with the following vehicles models: 2013 – 2015 Buick Encore, 2013 – 2015 Cadillac ATS, 2012 – 2015 Cadillac ATS – 3.6L, 2014 – 2015 Cadillac CTS – 2.0T, 2012 – 2015 Cadillac CTS – 3.6L, 2004 – 2015 Cadillac CTS-V – 5.7L / 6.0L / 6.2L, Chevrolet and GM sierra.


  • Improved mileage and fuel economy
  • 2.8” higher definition color screen
  • Easy to use interface with five buttons
  • Eliminates downshift when climbing hills
  • Faster memory processor
  • Performance tuning for the economy, towing, daily driving, and extreme tuning
  • Multiple tuning levels
  • Ergonomically-designed
  • Backlit display
  • Improved horsepower, torque, and overall performance
  • No excessive downshifting when climbing hills
  • Compact design
  • Active fuel management control
  • Transmission tuning
  • Shift points and shift firmness
  • Cooling fan adjustment
  • Rev and speed limiter
  • Full Color, 2.8″ high-definition screen
  • User-friendly interface
  • Pre-loaded Superchips custom tunes
  • Various vehicle parameter monitoring
  • Compatible with other performance upgrades

Hypertech 32501 Diesel Tuner for 6.6 Duramax

Hypertech 32501

The Max Energy Power Programmer from Hypertech is your ultimate performance tool for improving your vehicle’s abilities, fuel economy, and engine efficiency. Feel the additional horsepower, improved torque, and transmission functions! You can raise the engine’s RPM limiter, read and clear DTCs, extend the engine’s RPM range, adjust cooling fan temperatures, recalibrate speedometer and odometer for replacement tires, adjust transmission shift points and shift firmness, etc.

Moreover, this device allows you to go back to your stock settings at any time you want, e.g. when you need to get back to the dealership. In case you see a “Cal not found” message on the Max Energy screen, you have to know that the 32501 model is Internet updateable, which means you can download the latest version of the software for free by connecting the device to your computer via a USB cord and going to and then to Support. Don’t forget to turn on your key in the ignition to the “ON” position without fully turning the vehicle on. The device is used for only one vehicle at a time, but as mentioned before, you can always get back to your stock settings.


  • Model – 23501
  • Weight – 1 lb
  • Dimensions – 8.8″ x 5.3″ x 2.3″
  • Installation instructions, software CD, and USB cable included

Vehicle fitment

  • 2006-20015 GM 6.6L Duramax


  • Low EGTs
  • Easy engine tuning
  • Ultimate performance
  • Greater fuel mileage at half-throttle
  • Powerful towing
  • Three power levels
  • Plug-and-play installation
  • Improved fuel economy
  • Reads and clears DTCs
  • 0-60 throttle restriction
  • Cooling fan adjustments
  • Quickly return to stock settings
  • Top speed and engine RPM limiter
  • Optimal tuning modes for instant performance gains
  • Internet updatable
  • Automatic transmission shift adjustment
  • Shift point and shift firmness adjustments
  • Speedometer adjustments
  • Affordable price

SCT Performance 40490 Diesel Tuner for 6.6 Duramax

SCT Performance 40490

The BDX performance programmer from SCT is ready to share some cool custom tunes with your vehicle to unleash its true power! You can choose from three tuning levels (Street, Tow, or Performance), dyno-proven, street-tested tune files, and store up to 20 custom tunes from thousands of SCT’s tuning dealers all over the world.

Take full control of your truck and use the offered features when you like, whether it’s fuel economy, towing, speedometer or transmission shift point adjustments, diagnostics, real-time stats, parameters recording, data logging, speed limiter removal, idle adjustments, or gauge monitoring.

The device is ridiculously easy to install just like you always knew how to do that. Keep track of the latest tunes via WiFi connectivity and enjoy using this compact and conveniently designed device with a full-color display to gain more horsepower and torque for on and off-road conditions.


  • Model – 40490
  • Weight – 1 lbs
  • Dimensions – 5.5″ x 2.8″
  • Includes BDX device, OBDII adapter plug, USB cable

Vehicle fitment

  • 2006-2010 GM 6.6L Duramax


  • Compact design
  • Full-color display
  • Monitoring of engine parameters
  • Data logging and diagnostics
  • Real-time stats and parameters recording
  • Easy Wi-Fi tuning updates (Internet updateable)
  • Includes dyno-proven performance tune files
  • Stores up to 20 custom tunes
  • Easy and fast installation

HP Tuners MPVI2 M02-000-02 Diesel Tuner for 6.6 Duramax

HP Tuners MPVI2 M02-000-02

And now, we have something different for you. The MPVI2 tuner is one of the most recent, powerful diagnostic and scanning tools in the industry. The unit requires a laptop/PC to read, edit, and write your vehicle’s software.

The operation is pretty simple – you just follow the included instructions which tell you how to use the device – it’s nothing too complex – you just register on the official HP website, create your account there, and start using your MPVI2 tuner. This particular model also comes with two universal credits which you can use for different vehicles.

The device comes with a VCM Editor that allows reading vehicle control modules’ flash memory and adjusting various parameters e.g. torque plan, spark tables, fueling, RPM limits, transmission shift points, and pressure, exhaust valve control, etc.

Then you can upload all the recent changes back to the control modules of your vehicle using the device. Apart from the Editor, there’s a VCM Scanner which is, obviously, a scan tool for comprehensive viewing, charting, and logging diagnostic data in real-time via the OBDII port. You can use it to clear diagnostic trouble codes, as well. And then there’s a Pro Feature Set which allows for additional features using the Pro-Link and Expander Hub.


  • Software 4.0 and USB cable included
  • Weight – 0.4 lbs (7 ounces)
  • Dimensions – 10″ x 10″ x 3″

Vehicle fitment

  • 2006-2010 GM 6.6L Duramax


  • 2 universal credits
  • Sleek and modern design
  • Multiple new features
  • Reads and clears DTCs
  • Bluetooth data logging capability
  • Expander Unit (external inputs logging ability)
  • Large internal memory (8 GB)
  • VCM Editor and VCM Scanner
  • Read, edit, and write your vehicle’s software (requires a laptop)

PPE 111010000 Diesel Tuner for 6.6 Duramax

PPE 111010000

This unit was designed and built exclusively for 6.6L Duramax, so it’s your perfect fit for sure. The PPE Xcelerator tuner provides decent HP and torque improvements and offers 3 horsepower settings – 40, 90, and 120.

You can raise your vehicle’s torque value up to 200 lb-ft, or tune your transmission, adjust the speedometer, read data, and clear DTCs in real-time. If you want to get more of your Duramax, then this tuner is definitely your #1 thing to try! It’s able to provide that special extra power when you most need it. You will love it as you feel the difference it makes and the additional power it provides for your Duramax.


  • Model – 111010000
  • Weight – 2.1 lbs
  • Dimensions – 10″ x 11″ x 5″

Vehicle fitment

  • 2001-2010 GM 6.6L Duramax 2500HD/3500HD LB7/LLY/LBZ/LMM Engines
  • 2001-2007 GM 6.6L Duramax Kodiak/Topkick LB7/LLY/LBZ Engines


  • Speedometer adjustments
  • 3 power levels of bonus horsepower and torque
  • Speed limiter adjustments
  • Adjustable gear ratio (from 2.73 to 5.13)
  • Reads and clears DTCs
  • Engine diagnostics
  • Transmission improvements (quick learn feature)
  • Internet updateable (USB side-plug)
  • DPF regeneration

DiabloSport 8200 Diesel Tuner for 6.6 Duramax

DiabloSport 8200

Take full control over your favorite truck with the Diablosport 8200! This unit represents the latest technologies and comes with a powerful DNA – it has tons of pre-loaded and pre-programmed features from the worldwide popular and trusted manufacturer to provide maximum power and efficiency. Diablosport is a record-breaker with an experience that provides high-quality products that are “ready to run” right out of the box.

The Diablosport 8200 is designed to make sure drivers are equipped with extra horsepower and ensure torque is available with certifications that bundles up the performance and compliance to deliver more of your car with the assurance that you are covered at the local smog or emissions center. The certifications are also crucial for the vehicle owners who would be Delivering daily and recreationally. However, Diablosport has invested in time and resource towards keeping your vehicle in compliance without sacrificing any power or cutting corners.


  • Manufacturer: Diablosport
  • Model number: 8200
  • Weight: 12.8 pound
  • Package height: 6.2
  • Package depth: 2.4
  • Package width: 5.5

Vehicle fitment

  • 2001-2016 GM 6.6L DURAMAX
  • GM Diesel, Gas, Except Motorhome, Handheld


  • Built to last for years (high-quality material casing)
  • Versatility (designed and engineered for various vehicles)
  • Fuel economy and performance benefits
  • Data logging
  • Calibrate speedometer for gear ratio
  • Calibrate speedometer for tire size
  • Cooling fan control
  • Fuel rich adjustment
  • Spark timing advance retard
  • Easy installation with OBD-II
  • Improved user-friendly interface
  • Full-color 2.8″ screen
  • Rev/top speed limiter adjustments/removal
  • Torque and shift points/firmness management
  • Reads and clears DTC

Warning: features vary by application.


What is the best tuner for a 6.6 Duramax?

Edge, Bully Dog, Hypertech are considered to be among the top tuner manufacturers for 6.6 Duramax. EFI live, Banks, and PPE is also a few honorable mentions.

Can you tune an L5P Duramax?

Yes. You can tune an L5P turbo-diesel engine (a new generation of Duramax engines) with HP Tuners VCM Suite 4.3+ and an MPVI2 via the OBD2 port. This will require 10 Universal Credits, an MPVI2 with the latest firmware, the latest version of VCM Suite, and an Internet connection.

Tuning Boxes

These are devices that change signals from sensors to ECM, in most cases being primitive “tricks” affecting the duration of nozzle opening and injection lead time, “cutting” the signal from the supercharging pressure sensor to avoid pressure error code.

There are different ways of connecting – the more elaborate devices are installed in 2 large plugs on the left diesel valve cap, the less thought-out devices are connected directly to the sensors. In some cases, these chips are able to consider automatic transmission slip degree and EGTs (exhaust gas temperature).

More decent examples are Van Aaken, Edge Juice, Bully Dog Dominator. The first one is especially good for+200 HP, which means a reinforced automatic transmission, the stock will live quite a short time under such power, the second one is the most balanced, knows how to monitor the temperature of exhaust gases, how the transmission feels, and how to work with an external LCD screen that displays multiple useful parameters.

Tuning box advantages

  • In many cases, you can change the power level as you drive, which is a relative advantage, somehow. Make sure you read your instructions first.
  • Exhaust gases and transmission slipping control is objectively a bonus that reduces the risk of diesel or Allison failure.

Pros and Cons

The programmer and tuning box cons are quite similar.

  • The developer’s lack of time is more pronounced among programmer firmware manufacturers. Changes of any table related to fuel or boost pressure require correction from 5 to 10 more tables, then a vehicle test and recording of some of the parameters. The most problematic place, by the way, refers not to power and torque acceleration but to fuel economy at the switches.
  • The impossibility to consider the availability/nature of hardware modifications. Stock and vehicle with full inlet/outlet, a good external fuel pump will require, mildly put, different firmware or sensor corrections.
  • Chronic disregard for the health of automatic transmission.
  • Inability to consider the personal tastes of a particular user and various vehicle applications.

In all cases, the firmware will differ

  • With the advent of a variable geometry turbine and the corresponding complication of interconnections at the “electronic” level, the “crookedness” of the finished firmware has become worse.
  • Fixing bugs takes a long time.

EFI Live

Objectively, this solution is higher than the first two.

EFI Live consists of a computer program that allows you to configure a large number of parameters.

When it comes to Duramax you really need like 20%, another 20% – for those who dig really deep. The list varies depending on the D-max generation, so there’s no point in listing the possibilities… Trust me, there’s more than enough.

Besides, we have a device similar to a program which allows the computer to “communicate” with the diesel and automatic control modules, to see a good set of parameters in real-time (the desired and current fuel pressure in the ramps; often unclear (at first glance) lags are actually connected with the pressure “sagging”), to copy (if not password protected) and upload the firmware. To program this or that vehicle you will need a VIN-license which is not free, otherwise, you can only “read” stock firmware.

The process of thinking on, not to mention writing firmware, is not easy. Some information is collected piecemeal on the Internet, some of it remains the know-how of respected tuners, and then there is enough pure garbage as well. After that, computer sit-downs and vehicle tests follow. The further you get into all this, the more you realize you don’t know sh…anything yet… It’s just a matter of time and desire, though.

There are 2 and 5 position switches (DSP2 & DSP5) that allow you to switch between programs on the go. Not to forget, that here you have to give the automatic transmission some time for the adaptation of some things, but the possibility remains pleasant anyway.

EFI has pros and cons, too. Let’s start with the second

  • VIN license and tuner time cost money. No less than a programmer or a tuning box. Hardware modifications have a directly proportional effect on tuning time.
  • The necessity to meet, read stocks, talk about what you need from your vehicle and how it shall be used. The alternative is to buy a programmer that allows you to fill in the firmware received by e-mail via the OBDII port and communicate by the same e-mail.
  • The chances to spoil something by inability or ignorance are quite high.

EFI advantages are as follows

  • Almost limitless engine block control and transmission adjustments; this is where GM stands higher compared to Ford and Chrystler.
  • The ability to consider any configuration on the “hardware”, up to a combination of a pair of turbines and fuel injection pump assembly with savagely built automatic transmission, fuel system, etc.
  • Fast bug detection.


The LB7’s applications are the Chevrolet Silverado HD, GMC Sierra HD, medium-duty GMC Topkick, and medium-duty Chevrolet Kodiak. The main issues with the LB7 were injector failure, which was frequent.


During 2004, the LLY phased out the LB7 and continued production until 2006. The LLY featured in the Chevrolet Silverado HD, GMC Sierra HD, Hummer H1, Chevrolet Kodiak, and GMC TopKick models. This was the first emissions controlled Duramax which was integrated with the Allison 1000 5 Speed or the ZF 6 speed manual transmission.


The 6.6L Duramax LBZ’s replaced the LLY but lasted for a very short time. The LBZ is found in the Chevrolet Silverado HD, GMC Sierra, HD, Chevrolet Kodiak, and GMC Topkick. The LBZ is the aftermarket “hot rod,” and is the last model produced without a diesel particulate filter.


The LMM arrived mid-2007 model year, phasing out the LBZ. This model came with a new diesel particulate system requirement that provided “active regeneration” to regularly clean the DPF by literally burning the collected material.


In 2011, the LML Duramax was released. This latest version of the 6.6L Duramax comes with advanced emissions equipment, which uses diesel exhaust fluid injection to reduce nitrogen oxide emission levels by 63% over the previous LMM powered trucks. It is said that the LML uses 60% newly designed components. Including an upgraded engine block casting, oil pump, high strength pistons, and connecting rods, main bearing design, and re-routed oil passage circuit.


This is the latest model, introduced in 2017. The LP5 delivers 445 horsepower and 910 lb-ft of torque. The Duramax L5P replaced the LML for the 2017 model year Chevrolet Silverado and GMC Sierra HD pickups. This model delivers 48 horsepower and 145 lb-ft of torque more than the LML. Its stand-out feature also includes electronically actuated solenoid injectors replacing the standard piezoelectric injectors that were used in all models starting in 2001.

Tire Size

Between 2001-2010 GM trucks left the factory with lightweight 16-inch wheels and 30-inch highway tires. As such, a large percentage of truck powers upgrade their tire size with aftermarket options, these were usually larger than 35”. A change in the tire size means you need to change the engine tune to accommodate the new set of wheels.

What can be tuned?

Most modern tuners will let you calibrate every engine part and all electronic components for performance and comfort. This includes Camshafts, Cold air intakes, Cylinder heads, Fuel injectors, Full exhaust systems and headers, Intake manifolds, Nitrous systems, Rear gear changes, Superchargers/Turbochargers, and Throttle bodies. As well as windows, locks, alarms, etc.,

Custom, Canned, and Dyno

There are three types of tunes available, these are:

  • Canned: A generic preset tune that comes with the device.
  • Custom: A specially written tune, either prepared by a company or made by a professional.
  • Dyno: A shop prepared tune, where the tuner dials it in real-time.

I always suggest that you never buy a tune from an unknown source, and never tune by yourself. Custom tuning is for professionals that understand the nature of the entire operation; one change can destroy your performance, let alone an entire range of changes.

Tuning Variants

There are two variants for tuning; one is the use of chips, which come with preset tunes that you can employ at the flick of a switch. These are closed circuits, which means you cannot make custom adjustments. The second variant is Tuners, which come with open circuits that allow you to make custom changes to specific options.

Is the 6.6L Duramax reliable?

Duramax 6.6L is known to provide durable and reliable performance for 19 years. Many owners consider it to be the best engine in the world. However, some owners claim that air may get stuck in the fuel lines or fuel starvation may take place.

What is the horsepower of a 6.6L Duramax?

The peak horsepower of a 6.6L Duramax engine (2011-2016) is 397 HP at 3,000 RPM. The latest GM 6.6L L5P V-8 model produces 445 HP.

What is the fuel mileage for a 6.6L Duramax diesel?

It mostly depends on your driving habits and gearing. The fuel economy of Duramax 6.6L (when running empty) ranges from 15 to 20 mpg.

Is the LB7 the best Duramax?

The LB7 proved to be one of the most reliable diesel engines ever produced. It was introduced in 2001 and replaced by LLY in mid-2004. It featured high-pressure common-rail direct injection and a unique design cylinder head. Moreover, the LB7 has proved to deliver more torque, be more durable and efficient in terms of fuel economy. However, a few common issues with this model took place. Namely, injector failures, blown head gaskets, overheating, and oil dilution problems.

What is so special about the LBZ Duramax?

The LBZ was introduced in 2006 and was the first Duramax to achieve up to 350 hp at 3,200 rpm and 650 lb-ft of torque at 1,600 RPM. The LBZ had a huge performance potential and support abundance.

It was the last model that was produced without a diesel particulate filter.

The LBZ featured more aggressive engine tuning, a higher-pressure fuel injection system, a more durable engine block design, increased piston pin diameter, a thicker (than its predecessors) connecting rod section, a variable geometry turbocharger, yielding a substantial increase in horsepower and torque over LLY (the previous model). It was available for only two model years (2006-2007). Then it was replaced by LMM, which was more efficient in terms of emission regulations.

Is the 6.6L Duramax a “big block”?

Not really. More like neither “small” no “big.”

Who owns Duramax?

General Motors. The 6.6L Duramax is produced by DMAX (GM and Isuzu joint venture (since 1998) which is located in Moraine, Ohio).

What’s better: Duramax, Power Stroke, or Cummins?

These 3 diesel engines share the same fuel requirements and systems. Both the 6.6L Duramax and Ford 6.7L Power Stroke are V8 engines when the 6.7L Cummins is I6 (inline-six-cylinder diesel engine). The Cummins has a better torque (1000 lb.-ft.) and is the oldest (since 1919) diesel engine. Ram trucks are known for the Cummins engine, Chevy has the Duramax, and Ford trucks run with the Power Stroke. In terms of fuel economy, Duramax is the leader.

  • In terms of horsepower: Cummins (400 HP), Duramax (445 HP), Power Stroke (450 HP)
  • In terms of torque: Cummins (1000 lb.-ft.), Duramax (910 lb.-ft.), Power Stroke (935 lb.-ft.)
  • In terms of towing power: Duramax (23.300 pounds), Cummins (31.210 pounds), Power Stroke (34.000 pounds)

How can you tell if you have the LBZ Duramax?

The 8th digit of the engine’s VIN number is “2” in LLY and the LBZ is “D.” Besides, the badges on the LBZ are typically blue, LLY has the red ones.

What year Duramax has the best fuel mileage?

The efficiency, in this matter, depends on factors like speed, driving habits, weight, towing, etc. So results may vary. But the stock LB7 2001-2004 engines are considered to be the most fuel-efficient (around 20 mpg on cruise control). However, a few modifications will provide the same mileage, no matter the engine’s year.

What does the LBZ Duramax mean?

LBZ is one of the RPO (Regular Production Option) numbers for Duramax engines. There was also the LMK, developed by GM for full-size half-ton trucks, but this engine was never brought to life.

Does the LLY Duramax have Injector Problems?

This was the case with the LB7. To avoid the same issues with the LLY, GM changed the valve covers for easy injector replacement. However, watch out for blown head gaskets.

How many miles can you get on the LBZ Duramax?

You should get around 350,000-500,000 miles on a stock truck without major engine repair. But keep in mind that modifying parts lowers the number.

How many miles does a Duramax last?

It depends on how treated and maintained. It is supposed to last as long as you are ready to spend the money to keep it running. Unless there’s a good reason to change it when something irreparable happens. Many drivers have over 700.000 miles on their trucks.

How many miles can you get out of an LLY Duramax?

The same case as with LBZ (or any other) – it all depends on how you treat it. Many owners have over 300.000 miles on their LLYs since 2005, without any major repairs.

What Allison Transmission is in the Duramax diesel?

Allison 1000 transmission which is the standard automatic transmission for the Duramax diesel since 2001.

How often do you change the oil filter on Duramax?

Every 10.000 miles or when you see the message “change engine oil” (as stated by the manufacturer). Some manufacturers recommend changing oil between 5000-7000 miles.

Are Duramax engines made in America?

Yes. All engines are produced by DMAX in Moraine, Ohio.

What Duramax is in 2019?

The GM 6.6L L5P Duramax was introduced in 2017.

What problems does LBZ Duramax have?

As some drivers claim, the most common troubles may be due to weak cast-aluminum pistons and wrist pin issues.

Are all 2006 Duramax LBZ?

No, there is also the LLY (engine code “2). In mechanical terms, both the LBZ (engine code “D”) and LLY engines are actually the same, with different tunes.

What oil does a 6.6 Duramax take?

Amsoil, Mobil 1, Delvac, Rotella (T6 full synthetic), Conoco Phillips (semi-synthetic) 5W-40 or 15W-40 engine oils also fit.

What years are LBZ Duramax?

The LBZ was introduced in 2006. Then, in mid-2007, came the release of the LMM.

Does 2002 Duramax have Allison Transmission?

Yes. Allison 5-speed automatic transmission.

What oil does GM recommend for Duramax?

The manufacturer strongly recommends Amsoil Heavy Duty 15W-40 full synthetic engine oil for all Duramax diesel engines, or Amsoil Heavy Duty 5W-40 full synthetic engine oil for cold weather.

What vehicles have Duramax engines?

Chevrolet and GMC trucks mainly. LLY is also used on Hummer H1 Alpha.

  • LB7 (2001-2004): Chevrolet Kodiak/GMC Topkick, Chevrolet Silverado/GMC Sierra HD
  • LLY (2004-2005): Hummer H1 Alpha, Chevrolet Silverado HD/GMC Sierra HD
  • LLY/LBZ (2006-2007): Chevrolet Silverado HD/Kodiak/Express; GMC Sierra/TopKick/Savanna
  • LMM (2007-2010): Chevrolet Silverado HD/Kodiak/Express; GMC Sierra HD/Topkick/Savanna
  • LGH (2010-2017): Chevrolet Silverado HD/Express; GMC Sierra HD/Savanna
  • LML (2011-2016): Chevrolet Silverado HD; GMC Sierra HD
  • L5P (2017): Chevrolet Silverado HD; GMC Sierra HD

What is the horsepower of a 2018 Duramax?

445 hp at 2,800 pm.

What year Duramax have injector problems?

The 2001 to 2004 model year Duramax LB7.

Is the Duramax diesel a turbo?


What size Duramax is in Colorado?

GM-exclusive Duramax 2.8L Turbo-Diesel engine (LWN). The dimensions are 25.4″(L) x 25.8″(W) x 34.1″(H). 2.5L 1-4 and 3.6L V6 options are also available.

What year Duramax have DEF?

GM has introduced the Diesel Exhaust Fluid injection system for Duramax in 2011.

How much HP does an LBZ Duramax have?

The LBZ produced 360 HP.

How much horsepower does the 2020 Duramax have?

445 HP.

How much HP does an LLY Duramax have?

310 HP.

What is EFI Live Duramax?

EFILive is a special tuning device/tool/software that is used to alternate computer parameters in the stock ECU and TCM in ’01-to-current Chevys and GMCs. This is how you access and adjust the data.

How much weight can a 2500 Duramax diesel pull?

That depends on distance, speed, and frequency. Initially the 2500HD tows around 14.500-15.400 pounds. But you can pull from 20.000 to 24.000 pounds if you upgrade the trailer hitch.

Does the new Duramax have glow plugs?

Yes. But will only come on when it needs to.

How much horsepower does a 2018 Chevy Duramax have?

2018 Chevy Duramax has 445 HP @ 2,800 rpm.

Did Chevrolet build a Duramax-powered Suburban?


How much torque does the new Duramax have?

910 lb-ft. at 1,600 rpm (2018 Duramax)

How big is the fuel tank on a 2017 Duramax?

The fuel tank capacity for 2017 trucks is 21.0 gallons for (mid-size) and 26.0-36.0 gallons (full-sized).

How much does a 6.6 Duramax weigh?

All 6.6L Duramax engines weigh approximately 835 lbs.

How does a Duramax diesel work?

Diesel engines operate much like a gasoline engine. Inside the engine, controlled combustion in a cylinder chamber causes pistons to move up and down, which forces a crankshaft to rotate. However, the combustion process is different when it comes to a diesel engine, due to the fact that diesel fuel is different than gasoline.

We are talking about spark-ignition (gasoline engines) vs compression-ignition engines (diesel) here. Diesel fuel gets into the combustion chamber at high pressure when the air inside this cylinder is compressed to a high-pressure level. There’s no need for a spark/spark plug to ignite the diesel fuel since the air inside the cylinder grows hot enough to do that.

Which Duramax gets the best mpg?

The first 2001-2004 models with the LB7 engine RPO marking have the best mileage.

When was the first Duramax diesel made?

Duramax has replaced the 440 lb-ft Detroit diesel with the 500 lb-ft LB7 in 2001.

Does Duramax have aluminum heads?

Yes. Always had. But that’s the last thing to worry about.

How many valves does a 6.6 Duramax have?

Four valves per cylinder.

How much oil does a Duramax 6.6 hold?

10 quarts (with filter).

What is LMM Duramax?

The LMM is an RPO for the Duramax engine produced in 2007, which famous for its emission-friendliness (up to 90% cut emissions compared to previous generations). The engine met strict EPA regulations for 2007. The engine featured the Allison 1000 six-speed automatic transmission, 365 HP @ 3.100 rpm, and 660 lb-ft @ 1,800 rpm. The dimensions of the LMM are 30″(L)x30″(W)x32″(H). It was replaced by the LGH in 2010.

What engine is in a 2002 Duramax?


What year did Duramax get EGR?

2004. The LB7 trucks did not have an EGR system (except for a California emission vehicle).

About the author

Glenn Freeman

The eagle-eyed autosports journalist, guest commentator, the proud owner of GMC Sierra 1500, auto parts & auto repair consultant. You can follow him on Twitter

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