 If you own a 2010 or newer GMC or Buick, you don't have to trade it in, but you will save $82.50 on in-stock 2024 Sierra half-ton AT4s or Denali half-tons equipped with either the 6.2 liter V8 or 3 liter Duramax diesel. Come see our great selection of Sierras as well as our complete lineup of professional-grade GMCs.