In Gran Turismo 4, the characteristics of the cars are realistically designed and calculated so that they handle to the "real-life" physics of that particular vehicle, taking into account weight, speed, friction, wind, and more. To further enhance the realism of the driving experience, new technology blends real-time action with a photo-fixed background to immerse you in real-life environments such as New York City, the Grand Canyon and others. Highly detailed vehicles and environment mapping create broadcast-quality graphics, from lights and competitor cars reflecting on your automobile to leafs on a tree shaking in the wind.

You will have the opportunity to race in an enhanced arcade and simulation mode based upon similar game mechanics from Gran Turismo 3 A-spec. In both modes, you will have access to experience more than 700 authentic automobiles encompassing manufacturers from around the world, with a range from vintage to modern vehicles. Courses include existing closed racing circuits to specially designed city courses, reaching a total count of up to 50 tracks.

The arcade mode allows you to compete against others or the artificial intelligence on select courses. The simulation mode allows you to start from the bottom and earn your way up the ladder as you acquire driving licenses, race to earn money, unlock cars and courses, buy and sell cars, upgrade parts and compete in various championships. Playable from both first- and third-person perspectives, Gran Turismo 4 offers advanced opponent behaviour to capture real-life racing and unpredictability of finishes.