All automakers test for noise, vibration and harshness (or NVH) during the development of new vehicles, but Ford Motor Company uses a portable "environmental chamber" that it can take to a specific plant to pull production vehicles from the assembly line for testing. In the case of this video, the portable machine was at Louisville Assembly Plant to test the 2013 Ford Escape during its early launch, but Ford also sent one to Mexico during the early build of the new Ford Fusion.
These mobile testing facilities are housed inside of semi trailers, and in addition to having four posts that can be positioned under each wheel to simulate driving over various roads, the chambers can also vary in temperature from 20 degrees below zero Fahrenheit to 140 degrees Fahrenheit. All of this can be changed and controlled using computers. During the tests, technicians and engineers sit inside the vehicle and listen for any squeaks or rattles. The benefit of having such a device on hand rather than sending the car to Dearborn is that problems can be detected earlier and resolved sooner.
Check out the video below to see how Ford's mobile quality control system works.