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How Automotive Fine-Tuning Works

Automotive Fine-Tuning Technologies

Fine-tuning used to be a not-so-fine part of the auto manufacturing process. Volvo, for instance, once used two-by-four pieces of wood and rubber mallets to get doors into the right position in the frame. For decades, bumps and lumps were "fine-tuned" with a series of rubber mallets, and gaps were less than precise.

But automotive manufacturing and fine-tuning have come a long way in recent years. Take, for example, the factory where Volkswagen built its high-end Phaeton model in the mid-2000s. The vehicle was constructed along an assembly line, but the conveyor belt moved slowly to ensure each job was done properly at each station. Robots assembled the drivetrain and suspension because these pieces were too heavy for people to maneuver precisely. These measures, such as the andon cord at Toyota, ensured that fine-tuning could be kept to a minimum at the end of the construction process. Once the Phaeton was completed, it was submitted to a water bath to check for leaks, something almost every manufacturer does to its finished cars. Next, it was put into a light booth where inspectors could check for gaps, and then the car was placed on a dynamometer and driven in place on rollers so inspectors could listen for rattles.

Every automotive manufacture uses the eyes and ears of its testers to fine-tune a finished vehicle, a method that's unlikely to go out of style. In fact, most automotive manufacturers use the same technology and equipment to fine-tune cars, so it's the people who are most able to improve the process.

Has all this fine-tuning made for better cars? You bet. Read on to learn how it makes a difference.