See also:

Interior
Compared with the old 626, the Mazda6's wider body translates into extra space for five occupants. The driver's seat adjusts through a 9.4-inch range, and the 60/40-split rear seatback folds down. ...

Engine Compartment Overview
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Substantially reduced road and wind noise
Many improvements were made to structural rigidity and powertrain NVH performance to provide a quieter, more pleasant ride, including the reduction of high frequency booming noise sometimes heard ...