Smooth, integrated shape results in a competitive aerodynamic Cd figure of 0.29 The A4 is up to 45kg lighter than its 80 series predecessor The 62-litre fuel tank is recyclable The sedan's boot is actually larger than the A4 Avant with rear seats in place Four-link front suspension design is based on the luxury A8 series Geometry of the front suspension is designed to eliminate front-wheel drive kick-back at the steering wheel A simple, lightweight torsion beam axle is used at the rear Five-valve-per-cylinder technology means greater valve area for improved gas flow and better fuel economy compared to four-valve heads The long stroke engine design of 1.8-litre, 20-valve, four-cylinder is used to promote torque output across the rpm range Dual front airbags are standard on all A4 models All A4 models come with climate control air-conditioning, central locking and power steering