Hi everyone, new to the site and new Duramax owner (5000mi). Has anyone tried a Bullydog programer on the LML and can you tell me likes and dislikes. Also does anyone know of any other programers that will work with the LML.
If you install one and set it back to STOCK before any service work is performed, can they tell you had it on there? I was told by Bullydog's tech that they can only tell that you accessed the ECM such as when you hook up a ObdII scanner. Is this true?
Thanks

i thought the computer counted key strokes & everytime you loaded a tune-program it reset the keystrokes to 0.. i'm sure their other ways they can ck.when i was running my ppe tune the dealer did'nt care as long as it was'nt motor related. i had radio, power mirrors & glowplug fixed with tune installed.

Thread moved to fifth generation tuners/electronics forum.

The way it works is the ECM looks at the tuning on it and creates a calibration value of the tune. If it does not match what the number was at the last start up it saves the new value in the history. If the tune was not changed then nothing changes to the CVN number so no new item added to the history. The LML records the last 0 different calibration numbers. No way to defeat that feature. So if they pull up that table and see non stock GM CVN values they know it was tuned. So here they can void the warranty. If you need the warranty then it is best to leave it as is. But if you change it then you are on your own. Worst case to this is there is a defect in the engine like a bad cast piston that would of blown a hole even under stock power. Most likely once tune they can say tough luck even if all one may have done was run stock power and changed the tire size value so the speedometer was more accurate. So if you flash the stock tune back to the ECM and they need to pull up that info depending on the problem then GM can void it. As to just plugging in a device to the OBDII no to know if there was. One can plug in a code reader or something like an Edge Insight CTS and no problem there. All they do is read the data from the ECM. Once you write to it thats when you have voided the warranty.

Is the bullydog a module system or a full ECM tuner?

Brian

It would be a tuner with gauge and monitor functions as well as reading codes.
Dave

Then it to will write to the ECM if you tune with it. So if you remove it before service meaning like simple oil change or something they will not notice it. Even if in there they may not notice but if you do DPF delete then you will be needing to reinstall before service since you would reinstall stock tuning which will be looking for DPF system.

Brian

If I were to not remove any polution controls or change anything mechanically and only reprogram the ECM but were to return it to "stock" and remove the programer, would they be able to tell that I had changed the ECM settings?

Only if they look in the ECM history.

Brian

Bottom line is yes, if something happens and they want to look into the ECM they will be able to tell that it has been modified.

If you want to play, you better be willing to pay.