14. This is the finesse area. Here the body is given an inspection to ensure that no dust or dirt has adhered to the body. If foreign material is found, it can be sanded and polished out. From this point the body continues on to the Hard Trim area. This is where things get even more complicated. Once the body is released from the body shop, a sequencing procedure is placed in motion behind the scenes that ensures that the various components of the vehicle are ordered and delivered to correspond exactly with the final assembly of that specific vehicle. In other words, there are several assembly lines working at the same time, and they all must be timed to deliver their product to final assembly at the correct moment. For instance, dashboards are being built, seats are being ordered and the frame, suspension, and powertrain are being built (we'll get to chassis assembly in a minute).
15. General Assembly Area Manager Gary West, a 27-year veteran of GM, took us through the rest of the process. This is the Hard Trim area, and this is where the doors and liftgate are removed from the vehicle so they can be sent to another line to be "built." Items installed in the Hard Trim area include the sunroof, roof rail, airbags, interior moldings, third seat, and instrument panel (which come from an in-house instrument panel assembly line). Here you can see a worker guiding a sunroof assembly through the windshield opening of a body. Interesting fact: There are hundreds of fasteners installed in the final assembly process. Computers monitor the torque pressure of each fastener as it's installed to ensure it is tightened to spec. If a fastener isn't correctly torqued, the assembly line stops until the proper torque is achieved. This guarantees a 100 percent perfect torque rate of all fasteners.
16. Here you can see a worker installing an overhead DVD system in the Soft Trim area. Items installed in the Soft Trim area include glass (the windshield and quarter glass are installed robotically), center console, carpet, and seats. This is also the area where the assembled doors and liftgate are reinstalled. Because many of these installation procedures are repetitive, yet done by hand, GM has worked hard to devise ways to make each job easier and safer. For instance, this worker glides into the moving vehicle while seated on a trick device that eliminates the need to physically climb into each vehicle and install the product. Further, a substantial amount of work was incorporated into the design of the vehicle in an effort to aid in its assembly.
17. Here is a completed body that is ready to be married to a chassis. | 
18. At the same time the body is being built, its corresponding chassis is also being built. Here you can see the chassis assemblies as they arrive at the plant from an outside supplier. | 
19. The chassis travels down the assembly line inverted. As it moves along, components like the suspension, axles, driveshafts, rack-and-pinion steering, fuel tank, brakes, and hoses are all installed. The chassis is then turned right-side-up by machinery for the installation of the engine, transmission, transfer case, radiator, wheels, and tires. Interesting fact: The assembly line that mounts, balances, and adds the tire-pressure monitoring sensors to the wheels and tires produces a complete ready-to-roll unit every 12.5 seconds. |