Try turning the traction control off next time. Press that button once and hit the gas and go. My old 08 Sierra Denali would get a little testy in snow and disabling the traction control let the tires spin a little and the front tires would then kick in. I had cooper zeon tires, not the best in snow. Traded that in on a Yukon Denali and the Yukon is a beast in the snow even with the 22" Bridgestone Alenza tires. Even after new tires you may find it gets going from a stop if you are struggling to just by turning off the traction control.