Mazda introduced a brand-new sedan in 2003 to replace its 626 model. Expected to rival European cars in ride and handling, the Mazda6 was built on an all-new platform. Developers used competitive models as benchmarks, including the BMW 3 Series, Honda Accord and Toyota Camry.

In spring 2004, five-door hatchback and wagon body styles joined the lineup. Buyers got a choice of two engines: a 2.3-liter four-cylinder that produced 160 horsepower or a 220-hp, 3.0-liter V-6. One of two automatics or a manual transmission could be installed.

For 2005, entry-level sedans and hatchbacks gained standard antilock brakes and traction control. The available automatic transmission on V-6 models became a six-speed unit. All models except the Mazda6 i base sedan adopted standard side-impact and side curtain-type airbags.

All three body styles received an exterior redesign and interior updates for 2006. The optional Sport AT automatic transmission on four-cylinder models has been upgraded from a four-speed to a five-speed unit. Mazda's V-6 engine now produces 215 hp at 6,000 rpm and 199 pounds-feet of torque at 5,000 rpm.

Performance-oriented Mazdaspeed6 sedans hit showrooms in late summer 2005 as 2006 models. The Mazdaspeed6 is listed separately in the cars.com Research section.