Hi im new to the forum, but not to duramax's. I have an Lbz, but i was wondering what is holding back tuning for the LML engines. I know its the ECM, but what specifically is holding it back. how can we get past it? is funding towards the lml the reason? and did H&S crack the code? or do you have to crack more codes? meaning is the code that H&S have different than what you need to fully unclock the ECM? has anyone ever reached out to GM about the tuning? saying its beneficial?