Diesel exhaust fluid (DEF) is nothing new. GM’s Duramax-powered Chevrolet Silverado and GMC Sierra 2500HD and 3500HD pickups have had used the stuff since 2011. So has Ford’s F-Series Super Duty.

The company has announced its working on an all-new cat-back exhaust system for the 2019 Chevrolet Silverado 1500 and 2019 GMC Sierra 1500.