The 2003 Nissan Altima is a part of the sedan's third generation. It is available in four trims: 2.5, 2.5 S, 2.5 SL, 3.5 SE, and 3.5 SL. These designations primarily refer to the engine being utilized. The 2.5 series uses a 2.5 liter 4-cylinder engine that generates 175 horsepower, while the 3.5 series utilizes a 3.5-liter V6, producing 240 horsepower. Transmissions include a 5-speed manual, offered in 2.5 S and 3.5 SE, and a 4-speed automatic available in all trims. The Altima was redesigned for 2003, growing significantly in dimensions to move from the compact class to midsize. Notable interior tech features include an AM/FM audio system with CD player and power accessories. Safety equipment consists of dual front airbags, with optional side-impact and curtain airbags, and antilock braking available in V6 models.