BMW 4 Series (2016) is 3 mm (0.12 inch) wider and 114 kg (251 lbs) lighter than BMW 5 Series Gran Turismo (2018).
BMW 5 Series Gran Turismo (2018) is 245 mm (9.65 inch) longer, 85 mm (3.35 inch) higher and has 85 liters (3.00 ft3) bigger cargo space than BMW 4 Series (2016).