GM D platform
 The D platform or D-body was an automobile platform designation used from at least 1936 until 1996 and exclusive to GM's most luxurious brands; Cadillac and Buick. It was closely related to the GM B platform and C platform. For the majority of its existence the D-Body represented the largest Cadillac (Fleetwood Series 75 or the Fleetwood Limousine).