Sierra 2500HD SLE Extnded Cab and 2012 GMC Sierra 2500HD. Compass Emergency communication system and Heated door mirrors. Are you looking for a reliable used vehicle? Well with this great-looking and fun 2012 GMC Sierra 2500HD you are going to get it.. This terrific GMC is one of the most sought after used vehicles on the market because it NEVER lets owners down. Ask about our preowned superstore one year maintenance lifetime inspections with every preowned vehicle purchased. Prices only good for day they appear. All prices are subject to change. We cannot extend special Internet pricing without a printed copy of the online pricing the in-store price may exceed our special online pricing.