By Tony Whitney

Recent reader queries about the business of “platform sharing” by automakers prompts another look at this fascinating side of the business.

Platform sharing has been a major factor in the auto industry for some years now as automakers battle to get the best possible products to the marketplace at prices people can afford. The new car business is highly competitive and every avenue is sought to keep costs down without reducing quality or durability.

Using shared platforms means that automakers can build a wide variety of vehicles on a similar basic structure, keeping costs within bounds. Some automakers have bounced back from near-oblivion by adopting platform sharing techniques and others have cleverly adapted existing vehicles to products dramatically different from the ones from which they were developed.

What we’re talking about here, incidentally, is not the widespread “badge engineering” that proliferated during the 1970s and 80s among manufacturers at home and overseas. This much-maligned process involved taking identical cars and creating “new models” by adding minor cosmetic changes and fresh model identification.

In contrast, platform-shared vehicles can be dramatically different from one another and in some cases, there are even minivans, sedans and SUVs sharing similar platforms.

In general terms, the platform is the underlying structure of a car, station wagon or light truck and includes the engine and transmission, suspension parts, steering and various other mechanical components. The most common variable is the engine and some basic platforms can be built up with anything from an economical 4-cylinder to a large, performance-oriented, V8.

Audi A3
2006 Audi A3

2006 Volkswagen Jetta 2.0T
2006 Volkswagen Jetta 2.0T. Click image to enlarge

As we’ll see, there are all kinds of variations in the world of platform sharing and as might be expected, the technology can be complex and highly-sophisticated.

One of the best examples of successful platform engineering is a range of vehicles built by Volkswagen. The platform that’s used for the popular Jetta sedan and Rabbit (formerly Golf) hatchback range is also the basis for the Audi A3 sedan and Audi TT sports car. The platform is even used for other products from the VW corporate family not available in North America like the Spanish Seat and Czech Skoda.

The popular Chrysler PT Cruiser was based on the company’s now-discontinued Neon sedan, but few people would figure this out just by looking at it. The reason Chrysler can produce an innovative styling job like this at an affordable price is simply platform sharing. If the PT had to be built from scratch on a unique platform, it would cost an awful lot more than its current sticker price.

The bad old days when cars using similar platforms shared dreary styling similarities seem to be over. There are Buicks, Pontiacs and Chevrolets that all share the same underpinnings, but from a styling standpoint, each has a very different character. And shared platforms present design studios with lots of opportunities for using their creative skills – without prompting the traditional clashes with engineering staff.

Using a single platform for a wide variety of models helps automakers compete more effectively. Prices can be held in check and common parts make it easier to distribute supplies to repair operations. It’s all about “economies of scale” and creating widely differing products with similar mechanical and structural components.

Most buyers don’t even know their new car might share a platform with another model which may be more expensive or possibly cheaper. The rest of the vehicle may be very different indeed – one variant may be designed as a family sedan and the other as a sports car.

There are even automakers that sell vehicles based on one platform on several continents. Some platform-shared vehicles from General Motors are sold under various “local” nameplates in North America, Australia, Europe and Asia.

Platform sharing can even be carried out with vehicles having widely varying roles in life. The Toyota Sienna minivan, for example, is based on a Camry sedan platform. Probably better known is the fact that most large sport utility vehicles are based on rugged pickup truck platforms. The Ford Explorer and Expedition are built on F-Series pickup truck platforms, while the Dodge Durango SUV owes its origins to the Dodge Dakota pickup. There are similar scenarios all round the industry.

Another benefit of platform sharing is that it lends itself to advanced assembly line techniques now in use at all major automakers. Common basic components have helped speed development of the “just in time” system of sub-component supply, which involves vehicle parts arriving on the assembly line exactly when they’re needed and not a moment sooner – or later. There’s no wasted storage space or costly inventory control.

Ask an auto designer or engineer nowadays about which platform a new model is based on and you might get a fairly complex answer. The fact is that platform sharing has become even more sophisticated over the last couple of years as engineers have developed ways to achieve even greater flexibility using a basic platform.

Today, many shared platforms have different wheelbases and track widths. Even so, manufacturing technology is now so advanced vehicles from different ranges can be produced on the same assembly line, even if some of the major platform dimensions differ.

The shared platform process is not a crafty move by automakers to make more money by designing fewer basic vehicles. In today’s marketplace, it’s really the only way to compete successfully and the main reason we don’t have to come up with a lot more cash for that new sedan, SUV, minivan or truck.

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