How to Install an MM3 Diesel Tuner

In this visit to the shop, we’re going to walk you through how to install an MM3 diesel tuner on your common rail Dodge truck. In another post, we’ll go over installing an EFI Live tuner. These are emission compliant tuners for common rail diesels.

How to Install EFI LIVE and MM3 Diesel Tuners - Step by Step! | Power Driven diesel


MM3 Tuner -- What’s Included

When you order an MM3 tuner through us, you’re going to get everything you need to install the tuner and control for your truck. The box includes:

MM3 Monitor
Communications Mod Box (Com Box)
Window Mount
Wiring Zipties
Data Port Plug for Shift on the Fly -- This is year specific. Make sure it will work with your truck.
Micro USB Cable
OBDii Cable
Micro SD Adapter

This should be everything you need to install MM3 on your truck.

MM3 Tuner Install

On 3rd gen and up, the shift on the fly is located between the fuel rail and master cylinder. It is ziptied to a wire harness and has a dummy plug in place. Remove the ziptie and dummy plug, then connect the shift on the fly wire. The wire then needs to be routed into the cab of the truck.

Next, we suggest removing the kick panel so you can install the com box and connect the shift on the fly wiring. Connect the shift on the fly wire (be careful, it can be delicate) to the com box, then connect the OBDii wire on the oposite side. Lastly, connect the micro USB cable from the com box to the monitor. The remaining ports are for accessories, such as an EGT gauge.

Once everything is connected, turn on your truck to make sure things are working and powering on. Go to the main menu and select ECM, then hit ECM again, then select “Get stock file for truck”. This is what we need to tune your truck. After pressing this, it should say “successful”. Finally, press “Exit”, then get ready to email us the file.

The two most common problems with getting the stock file are either not securly connecting the USB or the microSD card is not fully inserted.

Emailing Your Stock File

Once you have pulled the stock file from the tuner in your truck, it’s time to send the file to us. Simply remove the microSD card from the display, insert it into the SD card adapter and inster it into the USB drive on your computer.

Navigate to the USB drive you have just inserted into your computer and open it. Click the “Custom” folder, then the “Stock” folder, and inside is your stock file. Copy this to an email and send it to [email protected] Be sure to reference your name in the email so we can keep files organized. Note that you are not allowed to change the names on the stock files.

Adding Custom Tunes to 2003-2004.5 Cummins

If you have a 2003-2004.5 Cummins, you’re going to get four files back from us labeled Tow.ecm, Mean Street.ecm, Race.ecm, and Meanstreet.ecm. Save these four files to your computer.

Next, you will navigate back to the “Custom” folder on your microSD card, then to the ECM folder. Copy the four new ECM files into the ECM folder. Now you can close everything on your computer, remove the microSD and reinstall into your monitor. Then you can flash the tunes and you’re done.

Adding Custom Tunes to a 2005 or 2008+ Cummins

If you have a 2005 or 2008+ Cummins that you want to add custom tunes to, you’ll get a very similar set of files to what’s listed above. You’ll get an ECM file and three or four RTG files. You will put the ECM file in the ECM folder on your SD card. Then you put the RTG files in the RTG folder. You can now disconnect the microSD card and install it in the MM3 and flash the ECM file. Once this is done, the RTG files will be available under either the “Switch” function or the “RT” function on the MM3.

Adding Custom Tunes to a 2006-2007 Cummins

If you have a 2006-2007 Cummins, you will get a single file called “LPCSP5.ECM”. All you have to do is drop this in the “ECM” folder on your SD card. Once it is flashed, you can use the “Switch” function to select your tunes.

How to Create a Data Log on Your Tuned Cummins

All of our emissions compliant tunes have a data log. You simply go on your MM3 console, select “Log HS” or “Log High Speed” from the main menu. This will start a recording bar on the screen. We prefer these to be less than 30 seconds so we can determine any issues or areas for improvement with your tune. After about 30 seconds, hit “Stop” and your data log will be saved.

To the data log to us, simply remove your microSD card from your MM3, connect it to your computer, then navigate to “Log_HSPD” and you will see a file called “DL00001.dlg”. This is the file you want to send to us. Note, the number will change each time you create a data log. You will send us the most recent log each time you create one.

Tip -- Remove any saved tunes from your desktop after installation. Because of the way the MM3 works, we can’t rename any new files. Removing saved or old files removes the potential for confusion or mixing up files if we have to send you a retune or new tune.

Stay tuned for part two where we cover how to install EFI Live in your Cummins diesel.

If you have questions about installing a tuner, or anything else on your diesel, we’re here to help. Give us a call at 435-962-9555 or text us at 435-962-9506 or leave us a comment below. Don’t forget to follow us on YouTube, Facebook, and Instagram for more product tests. Leave us a comment below about what you’d like us to cover next.