Mitsubishi flexa-facturing: it's nothing but Normal; Mitsubishi builds six very different vehicles at its Illinois plant

Automotive Industries, Feb, 2003 by Rob Wilson

Six distinctly different car models come off the same single assembly line at Mitsubishi's only North American assembly plant, located amid the prairie grass and wildflowers of Normal, Ill.

With a production capacity of 240,000 cars per year, Normal cranks out the Dodge Stratus, the Chrysler Sebring, the Mitsubishi Eclipse, the Spyder convertible, the Galant sedan and the brand new sport utility vehicle, Endeavor, which was recently introduced at the Detroit auto show. Endeavor is the first model to enter production in Mitsubishi's new PS platform program.

Building Endeavor at Normal did require the installation of a trim pre-assembly line where SUV specific elements are assembled into the vehicle, but then it joins the other five models on the main trim line for completion. At Normal, it's strictly uno pro omni, one line fits all.

"The key to our industry leading flexibility is our variability reduction teams. We have twelve different teams driving improvements. They work continually on assuring manufacturing commonality," says Rich Gilligan, president and CEO, manufacturing division, Mitsubishi Motors North America.

"The improvement has been dramatic. We've had an 84 percent improvement in our scrap rate. We ranked very highly (third place) in the 2002 Harbour Report on assembly productivity. We have cut our supplier base virtually in half. We have right-sized Normal to execute the PS series as effectively as possible."

Gilligan sees flexibility as an absolute must for auto builders facing a future with increasing competition in every market sector. More sectors and more models in each sector drives volume down for individual models. The process must be simplified and yet must also be the ultimate in flexibility.

Endeavor is Mitsubishi's entry in the mid-size crossover SUV niche. This new PS platform is the foundation for Mitsubishi's Project America vehicles, which will include a new Galant sedan, Eclipse sport coupe and Eclipse Spyder convertible. These models start rolling out later this year.

Job 1 for Endeavor production was in mid-January and the first vehicle produced was donated to the U.S. Space & Rocket Center. It happens that the first Endeavor shuttle mission in 1992 was a joint effort between the U.S and Japan.

Like all models produced at Normal, the Endeavor is of all-steel unibody construction. Ordinarily, one thinks body on frame for an SUV. But this is a crossover and that requires the unibody.

The structure is reinforced strategically with support members. Large, thick, straight side members have an octagonal design with large cross section and this permits optimal strengthening of the cross member. The large under-dash cross member will efficiently disperse frontal impact energy minimizing cabin deformation.

Thick members are welded diagonally between the firewall and doorframe also reducing cabin deformation. The floorpan is done in thick steel with an arched design for stiffness, torsional rigidity and reduced cabin vibration. A large single piece reinforcement spans the rear suspension to control body flex for improved rigidity, handling and vibration. It also would reduce cabin deformation during rear impact.

Straight rear side members resist bending and flexing forces and also effectively disperse impact energy. Rear shock turrets are located near the rear side members to optimize the rigidity of the shock mounting location. This promotes superior chassis performance and safety. Doors, hinge mounts and B-pillar are also reinforced. Front and rear bumpers are executed with steel beams covered with energy absorbent foam.

All of which makes for a sturdy, stiff, crash worthy structure. For comparison, where the other body styles produced at Normal have approximately 3,000 weld points, the Endeavor has more than 4,000.

Mitsubishi says the Endeavor meets and exceeds federally mandated 30 mph frontal, 30 mph oblique and 35 mph rear collision tests. The Endeavor is primarily an on-road vehicle, but it is engineered for mild, off-road service as well.

The Normal plant is made up of five shops, including metal stamping, plastics, body, paint and trim/final assembly. Over 800 Fanuc robots are at work in the shops, although that number will be brought down to approximately 600 as the PS platform is fully rolled out. Normal is currently a two shift operation employing 3,400 associates.

The Normal facility was built by DiamondStar Motors, the Mitsubishi/Chrysler joint venture, and began production in 1988. Mitsubishi bought out Chrysler's interest in 1991. Subsequently DaimlerChrysler acquired 34 percent of Mitsubishi in 2000. Over its history the plant has produced 16 different models for total production of approximately 2.5 million vehicles.

Most major body panels for the six vehicle models are stamped in the Normal plant and most bumper fascias are injection molded there also, including service parts. The plant was expanded from 2.0 to 2.2 million square feet in 2001. This expansion centered on the body and stamping shop.