Is your truck up to the job? Performax Trucks are! A new standard has quietly been achieved The starting point is the strongest, most powerful GMC Sierra Heavy Duty pickups ever. With a proven powertrain and the new standard in quiet, comfortable truck interiors, pickup first technologies and cargo box innovations, the GMC Sierra Denali is now the premium duty breed of professional grade trucks. The redesigned cabin in the 2015 Sierra Denali combines triple door seals, inlaid doors and other refinements throughout the truck to create our quietest HD pickup ever. Sierra Denali's all-new instrument panel puts controls where they're most visible - at your fingertips - and information at the sound of your voice. Drive train and mechanical . 6.6 litre Duramax V8 diesel engine with direct injection . Allison 1000 6-speed automatic transmission . Independent torsion bar . 4WD, 2-speed transfer case Exterior features . Integrated wheel arch mouldings to protect against stone chipping . Sculptured stylingand triple door seals help reduce wind noise . Cornerstep rear bumper for easy access into cargo box . Ez-lift and lower tailgate . Side mirrors - chrome-cap heated, Interior features . Customizable 20cm driver display - choose from a menu of display themes and information . IntelliLink - seamless touch and voice-activated connection to digital content - from contacts and music playlists on mobile devices to apps like Pandora . Heated and cooled perforated leather-appointed seating . Dual-zone automatic climate control . More legroom for back seats and bigger back doors Safety features . Forward collision alert, lane departure warning and Safety Alert Driver Seat Optional . Four-wheel, four-channel, antilock disc brakes (ABS) . Hill Descent Control provides smooth controlled descent in rough terrain without braking . Six available air bags including single-stage frontal airbags, head-curtain side-impact air bags with rollover protection and seat mounted-side impact air bags Note: On Road Costs arenot included in the price shown as they will vary from state to state and based on registration category. All pictures are for illustration purposes, please confirm with dealer on actual vehicle and specifications.