GT-R 400 is a touring car racing game. It features two kinds of car types: production models and GT models. The races takes place on closed circuit tracks and the cars are entirely controlled from a third-person perspective. The driving experience can be customized with a number of gameplay options such as car damage, driving aids and automatic gears. Two licensed cars are available, the Ascari KZ1 and the Mosler MT900. Sixteen tracks are available and they cover three continents.
A number of game modes are available. The quick race mode is for players that want go straight to the action on the circuit. It's available for one or two players in split-screen multiplayer. The championship mode allows the player to complete in three different championships for each car type. Each championship consists of a number of races and in each race the player has to finish among the top three to qualify for the next race. Three retries are available for each championship. When all are used the player has to restart from the beginning.
The time trial mode is about beating a specific time limit that is set before the race. The game offers 15 time trials for the player to unlock. When both these and all championship modes have been completed, a 16th time trial becomes available. Beating it unlocks a secret supercar.