List of GM platforms

General Motors vehicles are produced upon a number of globally shared automobile platforms. In General Motors parlance, each platform is referred to as an architecture.

Beginning in the 2000s, GM instituted an architecture naming scheme using the English-language names of letters of the greek alphabet, for example, "Alpha." Despite this change in naming convention, many vehicles are still produced on platforms using the older, latin letter-designated naming scheme.

Under the older, latin alphabet letter architecture name scheme, General Motors applied each architecture to vehicle families aimed at similar market niches. For example, the E-body Oldsmobile Toronado personal luxury coupe was redesigned significantly through four generations from 1966 through 1992, but retained the same letter designation throughout that time.

In some cases, the architecture name was retained for a market segment even when the architecture diverged radically. In 1982, the GM A platform was re-designed, switching from rear-wheel drive to front-wheel drive. The former rear-drive architecture continued to be produced, but was re-designated the G architecture. In certain instances, GM has used varied letter designations for similar products. The recent G, H, and K architectures are reported to be closely related, but GM has given different letter designations based upon the model produced upon the architecture.

For the latin alphabet letter platforms, the architecture designation usually corresponds to the 4th letter of the Vehicle Identification Number. GM used these letter designations to identify service manuals, owner manuals, and other publications. In the past, the automotive press would promote visually similar car families based on their platform designation. (For example, the "X Cars".)

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