BMW 5 Series Gran Turismo (2015) is 163 mm (6.42 inch) longer, 218 mm (8.58 inch) higher and has 80 liters (2.83 ft3) bigger cargo space than BMW 8 Series (G15) (2018).
BMW 8 Series (G15) (2018) is 2 mm (0.08 inch) wider and 206 kg (454 lbs) lighter than BMW 5 Series Gran Turismo (2015).