GMC Sierra 3500HD (2018) is 835 mm (32.87 inch) longer, 158 mm (6.22 inch) wider, 257 mm (10.12 inch) higher and has 927 liters (32.74 ft3) bigger cargo space than Subaru Tribeca (2014).
Subaru Tribeca (2014) is 804 kg (1,773 lbs) lighter than GMC Sierra 3500HD (2018).