Although it's unclear how long it will take to resolve the parts shortage, GM doesn't have much time to sort it out, as a new Ford F-150 looms on the horizon. At launch, GM's fullsize trucks were offered only with a base 4.3-liter V6 and the 5.3-liter V8, but a burlier 6.2-liter V8 will be available soon. Interestingly, at least at the moment, GM truck buyers don't seem as willing to downsize to V6 power as buyers of the F-150, which gets some 42-percent of its sales from trucks equipped with its EcoBoost V6 engine (not including the normally aspirated base V6).
Working out the kinks in the Silverado and Sierra's supply chain couldn't be more important to the health of the company. Full-size pickups are a huge profit driver – in 2012, the trucks were said to make up about two-third of GM's total profits.