Under pressure from the federal government, General Motors is recalling more than 3.4 million big pickup trucks and SUVs in the U.S to fix a brake problem. The recall covers the Chevrolet Silverado and GMC Sierra 1500, 2500 and 3500 pickups from the 2014 through 2018 model years. Also included are the Cadillac Escalade from 2015 to 2017, and the GMC Yukon and Chevy Suburban and Tahoe from 2015 through 2018. GM says a pump in the power-assist brakes can put out less vacuum power than needed, increasing stopping distance and the risk of a crash. The recall comes after the National Highway Traffic Safety Administration began investigating in November of last year. Dealers will recalibrate the electronic brake control module.