An 8-speed automatic transmission debuting in the 2015 Chevrolet Corvette boosts fuel economy by 3.
5 percent over the six-speed it replaces and gives the General Motors long-running sports car an EPA highway rating of 29 mpg, its highest rating ever.
Tadge Juechter, the Corvette’s chief engineer, said a few more pounds of air pressure in the tires would have bumped the EPA rating to 30 mpg, but affected the car’s ride and handling. “We’ll be back next year and we’ll get to the 30,” he said Tuesday at a media event at GM’s proving grounds west of Detroit.
The GM designed-and-built 8-speed automatic, the 8L90, is also scheduled for installation in the certain 2015 models of the Chevrolet Silverado and GMC Sierra pickups and will likely see duty in Tahoe and Yukon SUVs.