Mercedes-Benz began revamping its top-selling model line with redesigned 2003 luxury sedans. E-Class wagons continued unchanged for the time being. Sharing a general look and some features with Mercedes' big S-Class sedans, the E-Class continued in V6 and V8 form. Against previous E-Class sedans, the new models were nearly an inch longer in wheelbase and overall, half an inch wider, fractionally taller, but no heavier. The E320 used an unchanged V6 engine, while an E500 with a 5.0-liter V8 replaced the 4.3-liter V8 in the prior E430. Both had rear-wheel drive. Every 2003 model included a five-speed automatic transmission with manual shift gate, antiskid/traction control, and antilock four-wheel disc brakes. Front and rear side airbags, and curtain side airbags, were also standard. So was Mercedes' TeleAid assistance system. Sedans featured Mercedes' new "by-wire" brakes, with electronically controlled valves that modulated pressure to individual wheels, to match driving needs. A conventional hydraulic brake booster served as a back-up. The E500 came with an air suspension--a first for this line. Also available for the E320 sedan, it offered three driver-selectable levels of firmness. The E500 rode on 17-inch wheels, versus 16s for the E320. A sedan Sport Package included aero lower-body cladding and special interior trim; and for the E320, 17-inch wheels. Linewide options included a rear-obstacle warning, and voice-activated cell phone and navigation systems. All E-Class models could be equipped with heated/ventilated front seats. Exclusive to sedans as first-time E-Class options, massaging "Dynamic Drive" seats had air bladders that selectively inflated to counter cornering forces. "Smart" cruise control, designed to automatically maintain a set following distance, was another sedan option. So was a twin-sunroof setup, consisting of a conventional sunroof over the front seats, a fixed-glass panel over the rear seat, and power sunshades for both. A solar-cell version ran an interior cooling fan. High- and low-beam xenon headlamps were newly available. So was Mercedes' Keyless Go system, which used a credit-card-sized transmitter that allowed unlocking and starting the car simply by touch. Rivals included the Audi A6/allroad quattro, BMW 5-Series, and Lexus GS 300/430. A new high-performance AMG-tuned sedan debuted late in the 2003 model year.