I work for Toyota at a manufacturing plant, so take this for what you will. Toyota uses what is called a Global Body Line in their plants. What this means is, one line runs two or more models. The FJC shares what is referred to as an underbody with the 4Runner, GX470, etc. The underbody is basically the floor pan. Now, the rear floor and center floor are different though. The rear floor is the cargo area, the center floor is the rear footwell area. However, they are run on the same line, on the same machines. The only difference is the robot pics up the shorter floor pieces or the longer floor pieces. But the MC(motor compartment), dash(what most people call a firewall) and the front floor is pretty much the same, with the big difference being the "dragonfly" which is the tranny tunnel and the stuff the seats in the front bolt to(it looks like a dragon fly before it is welded in). The side members are different(the outer body skin from the a-pillar back) and some of the inner pieces are different, but the investment is made. The employees are trained, the robots are programmed, the jigs are built. There is really NO reason to kill it in the middle of the run. They may cut the hijunka way back(hijunka is a Japanese word that basically means the build ratio like one FJC for every 5 4Runners), but they wont kill it as long as it is selling somewhat. To give you an example of the flexiblity of the GBL, the Camry, Camry hybrid, Solara Convertible, Solara Coupe(now extinct) and the upcoming Venza all have been built on the EXACT same line in the same day. This is why toyota is so flexible in the lean times.
