BMW 5 Series Gran Turismo (2017) is 161 mm (6.34 inch) longer, 218 mm (8.58 inch) higher, 9 kg (20 lbs) lighter and has 80 liters (2.83 ft3) bigger cargo space than BMW 8 Series (G15) (2018).
BMW 8 Series (G15) (2018) is 1 mm (0.04 inch) wider than BMW 5 Series Gran Turismo (2017).