We've already heard rumors that General Motors is worried about the 2015 Ford F-150 and it appears those fears have pushed them to speed up the development of the next-generation Chevrolet Silverado and GMC Sierra.
According to Reuters, the launch of the redesigned trucks has been moved up to the fall 2018. If this is correct, the current generation models will have a relatively short lifecycle of about five years.
Little is known about the trucks but they are reportedly being developed under the T1XX codename. They could feature smaller displacement turbocharged engines with stop/start technology but nothing is official as of yet. Previous reports have also suggested the trucks will feature aluminum bodies to help reduce weight and improve fuel efficiency.
The report goes on to say the next-generation Chevrolet Tahoe / Suburban and GMC Yukon / Yukon XL will be launched in the fall of 2019.