General Motors has announced that its 2015 Chevrolet and GMC SUVs and pickup trucks will come standard with an 8-speed automatic transmission. More specifically, we're talking about the Chevrolet Silverado, GMC Sierra, and GMC Yukon Denali/Yukon XL Denali models equipped with the 6.2L EcoTec3 V8 engine.
No word on the Chevrolet Tahoe/Suburban, however.
The GM-developed Hydra-Matic 8L90 8-speed transmission is approximately the same size and weight as the Hydra-Matic 6L80 6-speed unit. Its 7.0 overall gear ratio spread is wider than GM’s 6-speed automatic transmissions, providing a numerically higher first gear ratio to help drivers start off more confidently with a heavy load or when trailering. The 8L90 also enables numerically lower rear axle ratios, which reduce engine rpm on the highway.
This comes more than a year after GM and Ford entered a partnership to develop an all-new generation of advanced, 9- and 10-speed automatic transmissions for cars, crossovers, SUVs, and trucks. The new 8-speed could be a stepping stone between these and the current 6-speed box.
The 6.2L EcoTec3 V8 delivers 420 horsepower and 460 lb-ft of torque, allowing a maximum trailer rating of 5,443 kilos (12,000 lbs). As with other EcoTec3 engines, it seamlessly switches to 4-cylinder operation under lighter loads to improve fuel economy.
Source: General Motors
No word on the Chevrolet Tahoe/Suburban, however.
The GM-developed Hydra-Matic 8L90 8-speed transmission is approximately the same size and weight as the Hydra-Matic 6L80 6-speed unit. Its 7.0 overall gear ratio spread is wider than GM’s 6-speed automatic transmissions, providing a numerically higher first gear ratio to help drivers start off more confidently with a heavy load or when trailering. The 8L90 also enables numerically lower rear axle ratios, which reduce engine rpm on the highway.
This comes more than a year after GM and Ford entered a partnership to develop an all-new generation of advanced, 9- and 10-speed automatic transmissions for cars, crossovers, SUVs, and trucks. The new 8-speed could be a stepping stone between these and the current 6-speed box.
The 6.2L EcoTec3 V8 delivers 420 horsepower and 460 lb-ft of torque, allowing a maximum trailer rating of 5,443 kilos (12,000 lbs). As with other EcoTec3 engines, it seamlessly switches to 4-cylinder operation under lighter loads to improve fuel economy.
Source: General Motors
 |
| Photo: Chevrolet |