GMC Sierra 3500HD (2018) is 6 mm (0.24 inch) wider, 52 mm (2.05 inch) higher and has 575 liters (20.31 ft3) bigger cargo space than Toyota Tundra (2019).
Toyota Tundra (2019) is 115 mm (4.53 inch) longer and 193 kg (425 lbs) lighter than GMC Sierra 3500HD (2018).