BMW i8 (2015) is 29 kg (64 lbs) lighter than GMC Sierra 2500HD (2015).
GMC Sierra 2500HD (2015) is 1394 mm (54.88 inch) longer, 103 mm (4.06 inch) wider, 695 mm (27.36 inch) higher and has 1573 liters (55.55 ft3) bigger cargo space than BMW i8 (2015).