The W-platform (also known as the W-body) was a
General Motors automobile platform which underpinned both
mid size and
full-size front-wheel drive cars. Originally code named GM10, it began development in 1982 under Chairman
Roger B. Smith and debuted in 1987 with the
Pontiac Grand Prix,
Buick Regal, and
Oldsmobile Cutlass Supreme coupés. The four-door
sedan version was introduced for 1990.
Starting with the 2nd Gen 110.5 in wheelbase in 1996 it became a full-size platform as well as a 109 in wheelbase mid-size; from 2005 on the 3rd gen 110.5 in wheelbase full-size was the only version through its discontinuation in 2016.
History
The platform cost $7 billion to develop and was to replace all midsize cars produced by
Chevrolet,
Pontiac,
Oldsmobile, and
Buick on the
G and
A platforms. This ultimately did not happen; while the A-platform
Chevrolet Celebrity and
Pontiac 6000 were quickly discontinued, the A-body
Buick Century and
Oldsmobile Cutlass Ciera remained in production until 1996. The engineering work was done by the Chevrolet-Pontiac-Canada (CPC) group; also known as the small car division.
The plan was for seven GM plants that would each assemble 250,000 of the cars, or 21% of the total U.S. car market. It was badly executed from the start, but GM's 1984 reorganization, combined with changing market dynamics, wrought havoc with the program and it never recovered. By 1989, the year before the last of the original GM10's were launched, GM was losing $2000 on every car it produced.

The later revision of this platform was known as the MS2000 or simply the W2-Car. Early versions used a transversely installed, fiberglass mono-leaf spring combined with struts in the rear. The "generation 1.5" W-body models had updated rear suspensions that used coil springs instead of the transverse leaf spring design inspired by the
Chevrolet Corvette. For the 1997 model year the second generation W-body was released with a MacPherson strut coil spring design.
The W platform was updated in 2004 rather than being replaced by a stretched
Epsilon platform, as had been planned. Metal fabrication of the floor pan for W-body cars was performed at the
Parma Metal Center in Parma, Ohio. The cars were built at GM's
Oshawa Car Assembly. The
transverse use of GM's
LS small-block engine in the W-bodies was a major addition for 2005.
The GM W Platform was phased out with the production of the new long-wheelbase
Epsilon II platform. The last car produced on the W platform was the ninth generation of the
Chevrolet Impala, which was replaced by the Epsilon-based tenth-generation Impala, beginning in model year 2014. GM continued to produce the W-body Impala to fleet customers only under the name Impala Limited until production ended in May 2016.
Use
Vehicles using the W-body include:
* 1st Gen 107.5 in wheelbase (mid-size)
** 1988–1996
Buick Regal (2-door coupe, 4-door sedan)
** 1988–1997
Oldsmobile Cutlass Supreme (2-door coupe, 2-door convertible, 4-door sedan)
** 1988–1996
Pontiac Grand Prix (2-door coupe, 4-door sedan)
** 1990–1994
Chevrolet Lumina (2-door coupe, 4-door sedan)
* 1.5 Gen 107.5 in wheelbase (mid-size)
** 1995–2001
Chevrolet Lumina (4-door sedan)
** 1995–1999
Chevrolet Monte Carlo (2-door coupe)
* 2nd Gen 109 in wheelbase (mid-size)
** 1997–2005
Buick Century (4-door sedan)
** 1997–2004
Buick Regal (4-door sedan)
** 1998–2002
Oldsmobile Intrigue (4-door sedan)
* 2nd Gen 110.5 in wheelbase (full-size)
** 1997–2003
Pontiac Grand Prix (2-door coupe, 4-door sedan)
** 2000–2005
Chevrolet Impala (4-door sedan)
** 2000–2005
Chevrolet Monte Carlo (2-door coupe)
* 3rd gen 110.5 in wheelbase (full-size)
** 2004–2008
Pontiac Grand Prix (4-door sedan)
** 2005–2009
Buick LaCrosse/Allure (4-door sedan)
** 2006–2016
Chevrolet Impala/Impala Limited (4-door sedan)
** 2006–2007
Chevrolet Monte Carlo (2-door coupe)
External links
References
{{General Motors platforms
W