GMC Sierra 2500HD (2014) is 951 mm (37.44 inch) longer, 165 mm (6.50 inch) wider, 15 mm (0.59 inch) higher and has 1231 liters (43.47 ft3) bigger cargo space than Mercedes G-Class (2015).
Mercedes G-Class (2015) is 323 kg (712 lbs) lighter than GMC Sierra 2500HD (2014).