The 2008 Volvo S40 is a premium, compact sedan available in three trim levels: 2.4i, T5 and T5 AWD, each named for individual powertrains. For 2008, the S40 receives new styling and improved storage in the center console, apart from a few new features.

The 2.4i trim has a 2.4-liter, five-cylinder engine that generates 168 horsepower. It is coupled to a five-speed manual transmission, though a five-speed automatic is optional; and has a front-wheel drive. The T5 gets a turbo-charged, 2.5-liter, inline-five engine that produces 227 horsepower. Both front-wheel and all-wheel-drive T5 models come standard with a five-speed automatic transmission.

The 2008 Volvo S40 features a refined and reshaped front and rear. The front grille surrounds and rear bumper are bolder and more upscale. The redesigned floor console has more storage space, a more compact handbrake and a revised armrest for greater driver comfort. Nordic light oak wood inlays can now be specified for the 2.4i cabin as part of the select package. Aluminum inlays remain standard on the T5 and T5 AWD. These models have redesigned instrumentation with sporty watch-dial style gauges. An auxiliary input with MP3 capability, now standard on all models, has been repositioned under the center armrest for greater ease of use. A high-performance audio system, and Sirius satellite radio with a complimentary six-month subscription is standard on T5 models. Audiophiles will delight in the new Dynaudio package, which outputs 650 watts through 12 speakers. The Volvo navigation system with DVD map data and remote control remains optional.

Standard safety features include anti-lock disc brakes, traction control, stability control, front-seat side air bags, full-length head curtain air bags, and head restraints. In frontal-impact tests by the National Highway Traffic Safety Administration, the S40 earned four stars for driver protection and five stars for front passenger protection; in side-impact crash tests it received a five-star rating. In frontal-offset testing by the Insurance Institute of Highway Safety (IIHS) it was rated 'good'. Side-impact protection is addressed by the use of rigid cross members that form a three-way attachment between the leading edge of the A-pillar and the base of the B-pillar. Similar cross members are found in the rear doors as well. This system of energy absorption, along with the slim-design five-cylinder engines, is called Volvo's intelligent vehicle architecture (VIVA), representing an innovative approach to vehicle safety design. Volvo's blind spot information system is optional on all trims.