Today on our 2013 GMC Terrain, we're going to be test fitting the Thule Big Mouth, a roof mounted bike rack, with part number TH599XTR. With our Thule Crossroads Roof Rack System already installed on the Terrain, we'll begin our test fit by placing the bike rack directly on to our load bars. At the front, we'll remove the T-bolt from the clamp on both sides, bring the clamps around the underside… see more >