Which Mario Kart game introduced vehicle customization with parts?

Which Mario Kart game introduced vehicle customization with parts? Mario Kart 7 introduced it.

Released for Nintendo 3DS in 2011, Mario Kart 7 added pre-race vehicle building to the series. Players could choose separate vehicle bodies, tires, and gliders, with each part changing statistics such as speed, acceleration, weight, handling, and off-road performance.

This system is sometimes confused with Mario Kart: Double Dash!! or Mario Kart DS, which offered distinctive characters, karts, or multiplayer features but not the same modular parts system. Mario Kart 7 also expanded racing beyond the track: underwater sections and gliding ramps became major parts of its course design.

The customization idea continued in later games, including Mario Kart 8 and Mario Kart 8 Deluxe, where players again combine bodies, tires, and gliders. However, Mario Kart 7 is the canonical first entry to introduce that parts-based vehicle customization.