Hi, I am a first time diesel owner. 07 LMM 4x4 crew Black. I am worried about the warranty with adding a tuner. I have heard that onstar checks diagnostics of the ECU at regular intervals, Is this true. Do we have to worry about big brother? I bought the PPE Tuner but have not installed it yet. Is it worth it to remove the muffler?

Thanks

old wives tail....onstar does not....can not...and will not blow you in for running a tuner

Actually, I would assume it is quite possible for them to retrieve and store that data. However, for a dealer or GM to use that information against you would open up floodgate of privacy issues that they couldn't win.

I have a tuner and nothing odd has appeared in my diagnostic reports. Everything is fine.