The 2006 Nissan Altima, part of the third generation, is a midsize sedan that offers a good mix of performance and practicality. It's available in five trims: 2.5, 2.5S, 3.5SE, 3.5SL, and the performance-oriented SE-R. Engine options include a 2.5-liter four-cylinder with 175 horsepower and a 3.5-liter V6 with 250 horsepower. The SE-R model gets a boost to 260 horsepower. Both engines can be paired with either a five-speed manual or a four-speed automatic transmission, depending on the trim selected. Standard features include power windows, locks, and mirrors, while higher trims add leather upholstery and a Bose audio system. Meanwhile, the SE-R trim gets sport-tuned suspension and Brembo brakes. Safety features for the 2006 Altima include standard front-seat side and full-length side-curtain airbags.