March 22, 2011 – Newly released photos of the GMC Sierra All Terrain HD Concept truck by General Motors are causing quite a stir at the Charlotte, Matthews or Monroe Liberty Buick GMC truck dealer locations. GM débuted the GMC Sierra All Terrain HD Concept truck at the North American International Auto Show this year. Newly-released photos of the GMC Sierra All Terrain HD Concept truck shows many changes since the vehicle’s previous photo release a few months ago. Included are the first photos of the design study’s interior; which has been upgraded to incorporate more luxurious and higher quality materials than the standard Sierra. GMC claims that the new concept vehicle is “an exploration of heavy-duty truck capability combined with greater off-road versatility,” according to the release.