Originally, GM used a Latin alphabet letter scheme to name its platforms, which were aimed at vehicle families in similar market niches. For example, the E platform Oldsmobile Toronado personal luxury coupe was redesigned significantly through four generations from 1966 through 1992, but retained the same letter designation throughout that time. During that span the vehicle grew from its original 211" as large as 220" then shrank to 188", and shifted from traditional body-on-frame construction to unibody, with the platform changing but not its designation.
In some cases an entirely new platform was developed but given the name of an existing one for marketing reasons, with the original being assigned a new designation. For example, in 1982, a ground-up front-wheel drive GM A platform (1982) was designed, with former rear-wheel drive GM A platform (1936) vehicles shifted over to it. However, the original A platform rear-wheel drive architecture remained in production, re-designated as the GM G platform. In certain instances, GM has used varied letter designations for similar products. The recent front-wheel drive 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.
In modern General Motors parlance, each platform is referred to as an architecture. Beginning in the 2000s, GM instituted a naming scheme for its global automotive architectures 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. Often these are informally referred to by their letter name and the term "-body", as in the GM "A-body".
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. It is common for the automotive press to describe visually similar car families based on their platform designation. (For example, the "X Cars".)
- GM 4200 - subcompact, FWD
- Gamma - subcompact, FWD
- Delta - compact, FWD
- Epsilon - midsize to fullsize, FWD
- Alpha - compact to midsize, RWD and AWD
- Omega - fullsize, RWD and AWD
- Y - sports cars, RWD
- GMT355 - mid-sized pickup truck, RWD and AWD
- GMT K2XX - full-sized pickup truck and SUV, RWD and AWD
- Lambda - crossover, FWD and AWD
- Theta - crossover SUV, FWD and AWD
- U - minivan, FWD
|GM platform nomenclature guide|
The GM nomenclature works as follows:
GM uses platforms to make a hierarchy of models aimed at different market segments. The following table attempts to place each shared platform in context. As General Motors has integrated worldwide operations, platforms are now shared globally.
GM reused some platform names between the front and rear wheel drive families.
GM also has/had a number of non-shared and international platforms:
- GM P platform - 1984–1988 Pontiac Fiero mid-engined sports car
- GM Z platform - 1991–2002 Saturn S-Series compacts
- GM/Fiat Premium platform - Alfa Romeo models, never used by GM
- Daewoo T platform - Daewoo Lanos, Daewoo Kalos, Daewoo Gentra
- Daewoo J platform - Daewoo Nubira, Daewoo Lacetti
- Daewoo M platform - Daewoo Matiz
- Daewoo V platform - Daewoo Leganza, Daewoo Magnus, Daewoo Tosca
Badge-engineered and non-GM products:
- GM M platform ( Suzuki) - Chevrolet Sprint, Geo Metro
- GM P platform ( Isuzu) - Chevrolet Spectrum, Geo Storm
- GM S platform ( Toyota) - Chevrolet Nova, Geo Prizm, Pontiac VibeH
- GM InsideNews Platform Guide Note: last updated March 16, 2006