The concept of sharing platforms among different automakers isn't new, but the flurry of automotive mergers, acquisitions and alliances over the past several years now is starting to produce definite plans.

Just last month Renault SA and Nissan Motor Co. Ltd. announced they have started co-development of the C-platform, part of the companies' planned platform-sharing project. Renault and Nissan, which is 36.8%-owned by the French company, plan to build 2 million vehicles off the shared C-platform, which includes Renault's Megane and Nissan's Almera and Primera. The project begins with Nissan in 2002, followed by Renault in 2004, with the the next-generation Megane.

The companies also collaborated on a co-developed B-platform, a project that began in July 1999. The B segment includes Renault's Clio and Twingo and Nissan's Micra and Cube.

The B platform represents 1.7 million units and the C platform 2 million units, comprising more than 50% of shared product volume. By 2010, the companies plan to share 10 platforms and eight engines, the platforms representing 90% of Nissan's worldwide sales.

B-segment consolidation started already, first in Nissan's Mexico plants. The Renault Megane Scenic now is built alongside the last-generation Sentra at the Cuernavaca, Mexico, plant. Renault now is gearing up for Clio production at Nissan's Aguascalientes, Mexico, plant, where Nissan builds the new Sentra.

Consolidation in South America will follow with Renault plants in Brazil producing Nissan vehicles. Nissan is investing $300 million in South America — mostly Brazil and Argentina — to build sales in the region to 150,000 units by 2010.

DaimlerChrysler AG officials insist Mercedes and Chrysler vehicles will never share platforms, but Chrysler very likely will share new platforms and components with Mitsubishi Motors Corp. and Hyundai Motor Co. Ltd., now partly owned by DC.

DC bought a 34% share in Mitsubishi last year, with platform consolidation as a main objective. The first new shared platform between Chrysler and Mitsubishi likely will be the so-called Z-car in Europe, also called World Car, in 2005. However Hyundai — 10%-owned by DC — was left out of the project, much to the Korean automaker's surprise.

Mitsubishi in the U.S. says it can't imagine merging any more platforms until it gets through the current product cycle. The two automakers already have a long history of working together and jointly building vehicles at an assembly plant in Normal, IL.

After announcing a linkup last year that included General Motors Corp. buying a 20% stake in Fiat SpA, the two companies are considering co-developing a number of sporty cars off the next generation Saab 9-3 and GM's Epsilon platform, partly because the GM platforms can pass various U.S. government tests. Possible new products include a front-wheel-drive Alfa Spider and more serious sports cars aimed at competing with Porsche. The two automakers also are combining development efforts of GM's next-generation Opel/Vauxhall Corsa minicar and Agila microvan with Fiat's Punto and possibly the Seicento and Palio.

Meanwhile, GM also continues to work with Toyota Motor Corp. in addition to its other Asian partners. The latest announcement here is the Pontiac Vibe sharing platform basics with the Toyota Matrix, built on a variant of the Corolla platform — and being built at New United Motor Mfg. Inc., Toyota's and GM's joint venture assembly plant in California. The Matrix will be built at Toyota's Cambridge, Ont. facility.