American automakers have launched an aggressive campaign to transform their aging assembly plants into state-of-the-art agile facilities that can produce multiple vehicle platforms on the same line. Flexible manufacturing is critical to allow automakers to respond quickly to changes in customer demand and adjust products according to market trends.

"Assembly plants must be capable of producing new products faster than ever before," says Dr. David Cole, director of the Center for Automotive Research (Ann Arbor, MI).

Traditional auto plants use fixed tooling that is designed to produce only two or three models of either cars or trucks. "That leaves manufacturers vulnerable to shifts in consumer demand," explains Cole. Flexible plants use robots, conveyors, fixtures and other equipment that can be reprogrammed or reconfigured to build vehicles with different designs, such as a four-door sedan, a two-seat sportscar, a minivan or a pickup truck.

General Motors

General Motors Corp. (Detroit) claims that it is rapidly improving its manufacturing flexibility. The automaker recently implemented a new technology called C-Flex in its assembly plants.

"C-Flex is a programmable body shop tooling system that is replacing body style-specific tooling," says Gary Cowger, president of GM North America. "In short, C-Flex allows multiple body panels, such as floor pans, deck lids, hoods and engine compartments, to be welded with the same set of programmable tools and robots. Model-specific tooling is not required."

With C-Flex, Cowger says GM is reducing the size of its body shops by as much as 150,000 square feet. He also claims that recent manufacturing improvements will reduce GM’s cost of introducing new products into a body shop by approximately $100 million.

"The benefits of C-Flex are plants that can build a higher variety of differentiated products at much lower costs," says Cowger. "By linking our technology, product development and manufacturing plans, GM is able to deliver great products to the market at a faster pace."

Initial applications of C-Flex were in the company’s Moraine, OH, and Oklahoma City, mid-size sport utility vehicle assembly plants. The next application of the C-Flex technology is at the new Lansing Grand River plant, where GM plans to begin producing the Cadillac SRX crossover vehicle this summer.

C-Flex technology also will be installed in other GM assembly plants including its Lordstown, OH, facility that will produce a next-generation small car, and its Orion, MI, plant that will assemble the next-generation Pontiac Grand Am.

"Improvements in manufacturing flexibility are also driving increases in GM’s manufacturing capacity utilization," says Cowger. "GM’s current North American capacity utilization is approximately 90 percent." The company has committed to increase capacity utilization to 100 percent by mid-decade.

"Assembly plants that are flexible generally have higher capacity utilization," explains Cowger. "Higher capacity utilization is a critical element of generating higher earnings and reducing structural costs."

According to Cowger, GM’s flexible manufacturing plants and its Global Manufacturing System (GMS) are directly linked to its product development strategy. "GM is moving to flexible, global vehicle architectures, which help reduce assembly plant complexity, increase plant efficiencies and enhance the company’s ability to quickly adjust product mix to better manage market fluctuations," says Cowger.

The GMS emphasizes a "sense and respond" approach, building flexibility into the system up front so that plants can quickly adjust product mix to respond to market fluctuations. "Our goal is to deliver a highly differentiated portfolio that meets a wide variety of customer needs and expectations," Cowger points out. "An integrated manufacturing and product design system allows us to respond quickly to customers’ changing preferences.

"Common global manufacturing processes allow GM to build flexible vehicle architectures. While allowing for a variety of subsystems, interiors and exterior designs, the system requires that all vehicles in the same portfolio must fit any assembly line designated to build that architecture.

"Flexible architectures allow GM to more easily build cars, trucks and crossovers off the same architecture in one or more plants," adds Cowger. For example, the Saturn plant in Spring Hill, TN, is assembling both the VUE sport utility vehicle and the ION sedan.

Another process that aids flexibility is "parallel processing." This technique is used at the GM plant in Ramos Arizpe, Mexico, which assembles the Buick Rendezvous, Chevy Cavalier, Pontiac Aztek and Pontiac Sunfire. "The crossover vehicles are built in a separate body process, come together with the other products through the paint shop, go into parallel lines through general assembly, and back together for final process and shipping," explains Cowger.

"Chaining" is a production process in which multiple plants build the same products. For example, GM’s Orion, MI, facility can assemble the Buick LeSabre, Buick Park Avenue, Oldsmobile Aurora and Pontiac Bonneville, while the Detroit-Hamtramck plant can produce the Buick LeSabre, as well as the Cadillac DeVille and the Cadillac Seville. "The LeSabre can be produced at either plant," claims Cowger, "helping optimize plant capacity utilization as demand fluctuates."


The ability to produce several products under the same roof will allow DaimlerChrylser’s Chrysler Group (Auburn Hills, MI) to save millions of investment dollars, as well as bring a new vehicle to market faster, with better quality and minimal downtime.

Chrysler’s Windsor, ON, assembly plant is in the process of moving the company to the next level of flexible manufacturing by adding the all-new Chrysler Pacifica crossover vehicle to the same production line as the Chrysler Town & Country and Dodge Grand Caravan minivans.

"With flexible manufacturing, the Chrysler Group will save nearly $100 million for the Pacifica launch, while simultaneously reducing tooling and facilities capital expenditures by approximately 40 percent," claims Tom LaSorda, executive vice president of manufacturing.

Savings will be realized by using the company’s worldwide resources and a total system approach. A combination of creative bidding on tooling, digital manufacturing and full asset-utilization will contribute to the overall savings. According to LaSorda, the company’s flexible efforts will support the addition of five new vehicles to the current long-range product plan.

"For the first time ever, a Chrysler Group manufacturing facility is able to produce two entirely different products on the same production line as a result of flexible manufacturing initiatives," boasts LaSorda. "Flexibility lends to better use of our capacity, which will ultimately increase our ability to meet market demand more quickly, with less cost, while enhancing our competitive position within the industry."

LaSorda says the key to Chrysler’s flexible manufacturing system is the order in which the body is assembled, using a unique underbody palette system in the body shop. The same flexible palette system has also been used at the company’s Sterling Heights assembly plant, which produces the Chrysler Sebring and Dodge Stratus, and the Toledo North assembly plant that produces the Jeep Liberty and Jeep Wrangler. "The same production system may be used to build sedans, convertibles, minivans, sport utility vehicles and sport tourers," says LaSorda.

"A flexible manufacturing system will give the Chrysler Group the ability to increase or decrease production with ease, depending on market demand, and ultimately move us closer to obtaining our additional one million units by 2011," LaSorda points out.

While the Pacifica will be built in the same plant as Chrysler and Dodge minivans, the vehicle will not be built on any one of the company’s short- or long-wheelbase minivan platforms. The Pacifica will be built on its own new, unique platform, but will use existing components. However, the vehicles will share several production processes as a result of the plant’s ability to accommodate a unique vehicle architecture.

For example, Windsor’s flexible body shop will use common processes of underbody framing and panel lines, paint systems and final assembly between the Chrysler Pacifica and Chrysler and Dodge minivans. A few unique body subassembly systems, such as engine box, underbody subassembly and body sides for the Chrysler Pacifica, are located in satellite areas within the Windsor plant.

LaSorda says Chrysler invested more than $300 million in the Canadian facility to accommodate Pacifica production. "The ability to build multiple products on the same line enables us to effectively build pilot vehicles in the assembly plant much earlier in the launch phase," adds LaSorda. That allows the company to train employees, as well as detect and address any remaining issues to meet quality goals.


During its centennial celebrations this summer, Ford Motor Co. (Dearborn, MI) will unveil its showcase of flexible manufacturing, the Dearborn Truck Plant. The new facility will be capable of producing up to nine different models from three vehicle platforms, making it Ford’s most flexible assembly plant in North America. Initially, the plant will build Ford’s popular F-150 pickup truck.

"Vehicles will be manufactured at the lowest costs in the shortest time possible," says Bill Russo, director of advanced manufacturing engineering. "Synchronous Material Flow (SMF) will support team-based production processes. These processes are designed to provide outstanding quality and minimize waste in a safe work environment that emphasizes employee empowerment.

"Although many plants use SMF to synchronize vehicle and supplier production at the same rate of customer demand, the Dearborn Truck Plant will use a combination of material delivery systems," adds Russo. "These include in-line vehicle sequencing and an automatic sequence and retrieval system that are designed to sequence units into a predictable schedule."

Russo claims this will allow Ford suppliers to more precisely plan deliveries. As part of the new fast-paced delivery system, truck docks will allow material unloading within a 15-minute window.

Ford’s team-based organization will deliver components to the assembly line at the same rate as product flow and will be committed to building to a specific schedule. "By using proactive problem solving and in-station process control, line operators have the responsibility for producing a product with no quality issues when it leaves their work cell," Russo points out.

According to Russo, the body shop assembly process at the new plant will be divided into a set of 16 distinct standardized cells, with each having a specific function. As few as several hundred components will be needed to build all 16 cells. "These cells are arranged to create subsystems, and these subsystems then make up a body shop," says Russo.

For example, while a pallet moves the vehicle body along the assembly line, one cell applies sealer or adhesives, and other cells handle welding. "Just like having a set of building blocks, we’ve standardized the process so that only 300 components are needed to create all 16 cells, and these different cells are put together to make up the entire body shop," says Russo. "That’s why the purchasing and operating efficiencies are so significant."

Only a portion of the product-specific tooling on vertical trays, horizontal gates or robot arms will need to be changed or modified, with the computers and robots reprogrammed. Most of the equipment, such as the structure, robots, controls and utilities will remain to build the next product.

Russo says the same type of standardization used in the body shop will be employed in final assembly. "Final assembly operations will have a standard sequence, with standardized workstations that can be changed or modified quickly and easily to accommodate new vehicle options or features," explains Russo.

"The standardized system results in economies of scale in equipment purchases, reduced variety and inventory of spare parts, and faster launch cycle," adds Russo. "The company can shift production and parts to other plants if needed. It’s easier to implement employee training with a standard system. Plus, it’ll be easier to apply best practices throughout the company’s assembly operations."