We’ve said it before, but it bears repeating here – GM needs to strongly defend its position as a leader in full-size truck sales. While the company shows progress on the passenger car and small SUV/crossover front, profit-heavy vehicles like the GMC Sierra pickup and Yukon utility vehicle continue to be crucial to a solid bottom line. Admittedly, shoppers are migrating to more fuel-efficient offerings, but GM is intent of preserving, if not increasing its share of this still lucrative, if smaller, segment. To that end, the 2007 GMC Sierra arrives with an attractive new design, a host of powerful engines pushing up to 400 horsepower, scores of desirable standard and optional features, and true truck capability equating to a 10,500-lb. tow rating, a bigger box, and a payload maxing out at 2,160 pounds. Every ounce of that pulling and hauling power will be necessary when the thoroughly redesigned Toyota Tundra arrives at the beginning of the year.