Filed under: GMC,Truck,Driveway Tests Continue reading 2021 GMC Sierra 1500 AT4 Driveway Test | How to use the GMC MultiPro Tailgate 2021 GMC Sierra 1500 AT4 Driveway Test | How to use the GMC MultiPro Tailgate originally appeared on Autoblog on Wed, 20 Jan 2021 11:20:00 EST. Please see our terms for use of feeds. Permalink | Email this | Comments Continue reading...