Not to steer the thread off course, but on a very related issue......
Something is to be said for purchasing prior year models that may still be in inventory with dealers. I purchased my 2016 model year in Sep of this year and received a HUGE discount, when compared to what they would let me have the 2017 for. I still received a 2 year warranty from date of purchase.
2016 Jay Flight SLX 264BHW
2013 GMC Sierra 1500 Ext. Cab/Z71/5.3L/6L80/3.42