
Photo of 2015 Chevrolet Silverado LTZ courtesy of GM.
General Motors will pair a new 8-speed transmission with its 6.2L V-8 engine offered on 2015 Chevrolet Silverado 1500, GMC Sierra 1500, GMC Yukon Denali, and Yukon XL Denali models.
The Hydra-Matic 8L90 automatic transmission replaces the Hydra-Matic 6L80 6-speed automatic transmission. The 7.0 overall gear ratio spread is wider than the 6-speed and provides a numerically higher first-gear ratio to help drivers pulling a heavy load during trailering. The 8L90 also enables numerically lower rear-axle ratios that reduce engine rpm on the highway.












