The 2009 Infiniti M receives more V6 power, and certain versions get a new 7-speed automatic transmission. These V6 and V8 sedans are the larger and costlier of Infiniti's two premium midsize cars. The M35 has a 3.5-liter V6 engine with 303 hp, an increase of 28 over 2008 versions. The M45 has a 325-hp 4.5-liter V8. Each is available with rear-wheel drive or all-wheel drive. AWD versions are dubbed M35x or M45x. Rear-drive M35 models have a new 7-speed automatic transmission. All other versions use a 5-speed automatic. Available safety features include ABS, traction control, an antiskid system, curtain side airbags, and front side airbags. Leather upholstery, sunroof, power tilt and telescopic steering wheel, and keyless entry/engine start are standard. Optional on rear-drive models is a Sport Package, which includes firmer suspension tuning, Infiniti's Rear Active Steer, sport bucket seats, and specific trim. Lane-departure warning, a heated power-reclining rear seat, and navigation system are among the options offered on all.