Has anyone compared the stock file from a 2017 with the stock file from a 2018 (both in the tune repository)? The cruise area specifically is pretty different considering the trucks are mechanically the same. In general the 2017 runs more timing, 6* in some cases. If I understand correctly the reduced timing on the 2018-2019 trucks reduces NOx production at the expense of fuel economy and soot production, so this was probably an emissions related change? This same difference is even more pronounced between the truck/chassis cab tuning granted the turbo is smaller so that might be related.