2015 Corvette Will Get The 8L90 Eight-Speed Gearbox

By Manoli Katakis

With the 2015 Corvette Z06 getting the 8L90 eight-speed gearbox to compliment its seven-speed manual transmission, everyone felt it was only a matter of time before the Corvette team rolled the new transmission into the Corvette Stingray. Today, Chevrolet announced just that, and buyers can expect the 8L90 in the Corvette Stingray beginning the 2015 model year. This wasn’t expected to happen until 2016.

The 8L90 was designed in-house and will also be built by General Motors in Toledo, Ohio, with expectations to improve fuel economy in the Stingray by five percent when compared to the outgoing, heavier six-speed automatic. The only difference between the type of 8L90 that the Stingray will use when compared to the Z06 are unique clutch and torque converter specifications matched to the lowered torque capacity of the base Corvette. The transmission controller analyzes and executes commands 160 times per second, which drivers will control via paddle shifters.

Performance-wise, the 8L90 promises faster shifts than that of the most world-class dual clutch transmissions, despite being a single-clutch unit. And example the Corvette team gave is that it will shift eight-hundredths of a second quicker than that of the dual-clutch transmission offered in the Porsche 911 at wide-open-throttle. And extensive use of aluminum and magnesium make it more than eight pounds, or 4 kg, lighter than the six-speed. Additionally, the 8L90 benefits from packaging efficiencies that DCT gearboxes can’t measure up to, which is one of the main reasons a dual-clutch hasn’t made it in the C7.