There are only a few minor changes to the Volvo S60 for 2004.  The 2.4T has been renamed the 2.5T, and it is now powered by the same engine as the AWD model.  The optional Sport Package now includes a speed-sensitive power steering system and bi-xenon headlights become optional across the board.

The S60 lineup continues with four variants this year: base 2.4, 2.5T, 2.5T AWD and T5.  A high performance R model also wears the S60 badge, but it exists as a separate model.  The Base S60 is powered by a 2.4 liter inline five, which supplies 168 horsepower and 170 pound-feet of torque. The 2.5T and 2.5T AWD S60s get a 2.5 liter inline five, which generates 208 horsepower. The T5's engine gains additional turbo power, for a total output of 247 horsepower and 243 pound-feet of torque.

The 2.4T and the 2.5T AWD are automatic transmission only, but the 2.4 and T5 models are available with both the five-speed manual and five-speed automatic transmissions. S60 fuel economy ranges from 22/31 mpg to 18/25, with mixed driving mpg estimates in the low 20s.

All S60 models offer adequate performance and above average interior comfort and functionality, according to reviewers and drivers.  Overall acceleration is impeded by slight throttle response delay and a mild torque steer on front wheel drive models.  The S60 is a solid performer, with respect to handling agility and steering response, but reviewers felt that it was not up to par with some of its German rivals.  Overall engine refinement is also lacking, compared to the V-6 units of BMW and Audi.