GM C platform, also known as the C-Body, was a
front wheel drive (FWD) automobile platform used by
General Motors
The General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. It is the largest automaker in the United States and ...
's Cadillac, Buick and Oldsobile divisions for their full-sized automobiles from 1985 through 1996, sharing a transverse engine configuration, rack and pinion steering and four-wheel independent suspension.
Significantly shorter, narrower, lighter and more fuel-efficient than the platform they replaced, the C Platform vehicles were noted for having nearly the same key interior dimensions as their predecessors and a much more nearly flat passenger compartment floor
— albeit with thinner seats and dramatically less upper
tumblehome
Tumblehome is a term describing a hull which grows narrower above the waterline than its beam. The opposite of tumblehome is flare.
A small amount of tumblehome is normal in many naval architecture designs in order to allow any small projection ...
, locating windshield as well as side glass closer to passengers.
Introduced in early 1984, the models were marketed as the
Oldsmobile Ninety-Eight
The Oldsmobile 98 (spelled Ninety-Eight from 1952 to 1991, and Ninety Eight from 1992 to 1996) is the full-size flagship model of Oldsmobile that was produced from 1940 until 1942, and then from 1946 to 1996. The name – reflecting a "Series ...
(11th gen),
Buick Electra (6th gen) and
Cadillac Deville (6th gen) and
Fleetwood (1985-90), and were manufactured at
Wentzville Assembly
Wentzville Assembly is a General Motors auto and truck assembly facility in Wentzville, Missouri, opened in 1983. Located at 1500 East Route A in Wentzville,
the 3.7 million square foot plant sits on 569 acres approximately 40 miles west of St. Lo ...
,
Orion Assembly, and
Lansing Car Assembly.
All C-Bodies used, V6 or V8 engines, GM's TMH440 transmission (initially), unibody construction — and all had been aerodynamically refined, with the Oldsmobile achieving a .383 drag coefficient.
Both the
H platform and C platform shared the same 110.8 in wheelbase. Later in the course of its development, Cadillac introduced C Body models with a 113.8 in wheelbase. Most C-body vehicles were ultimately replaced with cars on the related
G,
H, and
K platform designations.
The
Cadillac Series 75 limousine briefly made its return on this platform, stretched by 23.6" to a wheelbase of 134.4". Cadillac used the platform though 1993; Buick heavily revised the Electra, becoming the first generation
Buick Park Avenue (1991-1996), while still using the C Platform; and Oldsmobile marketed C Platform derivatives through 1990, notably the
Oldsmobile Touring Sedan
The Oldsmobile Touring Sedan (informally "OTS") is trim level of the eleventh generation ''Ninety-Eight'',a full-size car manufactured and marketed by Oldsmobile from 1987-1993 across two generations, both using the front-wheel drive GM C-platf ...
.
Models using the C Platform
References
List of GM VIN codes{{General Motors platforms
C