GMC Sierra 2500HD (2016) is 553 mm (21.77 inch) longer, 37 mm (1.46 inch) wider, 126 mm (4.96 inch) higher and has 1038 liters (36.66 ft3) bigger cargo space than Mercedes GL-Class (2015).
Mercedes GL-Class (2015) is 383 kg (844 lbs) lighter than GMC Sierra 2500HD (2016).