The current GMT920 full-size SUVs from General Motors are very likely to be the last of their kind from the Detroit automaker. Even though new fuel economy standards give the big trucks a break based on their footprint, radical changes are likely for the next-generation models. A fully-equipped Tahoe is well over 5,500lbs and a big part of reducing fuel consumption in the next few years will be weight reduction. One step in that direction will be a shift from the body on frame designs these vehicles have used since their inception over to a uni-body structure. Ford already declared that the next-generation Explorer will be a uni-body and GM has their Lambda platform crossovers which are nearly as large as the GMT920s. Sales of the Tahoe are already down 10.5 percent this year and that trend is likely to accelerate. The next-generation models that are due to debut around 2012 will almost certainly make the jump to a smaller, lighter platform. In fact, a distinct possibility might be an SUV derived from the Zeta platform like the Denali XT pickup concept that was shown at the Chicago Auto Show this year. Without the pickup bed and with a slightly taller roof, this design could likely shave nearly 1,000lbs off the current SUVs. Regardless of the design direction that GM follows, the maxi-sized SUVs and pickups will likely never reach the sales heights they once did, meaning that GM is planning to scale back production capacity. The current 1.7 million annual capacity will probably drop to somewhere around 1 million. GM recently announced plans to cancel one shift at each of four truck assembly plants. Going forward, that production will likely be consolidated to fewer plants.