Here is what our tunes look like for the LML.
1. Optimized Stock -Power delivery smoother than stock with near stock output -Refined timing tables for lower EGTs and higher efficiency
2. Heavy Tow Tune (+40)-Built for towing loads from 8000lbs to gross vehicle weight
3. Light Tow Tune (+55HP)- Built for towing loads under 8000lbs
4. Sport Econ (+110)-High performance street tune designed to balance performance and reliability-Throttle sensitivity increased for less throttle input, quicker shifting and less average RPM in daily driving situations
5. Race Tune (+135)- This tune represents the maximum effort a Duramax engine equipped with a stock turbo and stock injectors. A FASS 150 lift pump and gauges are highly recommended
You are correct. DEF will spray whenever the NOX sensor triggers it. Here is a great resource for emissions equipment: