|The 2007 Saturn Aura|
At the New York Auto Show, GM is unveiling the all-new 2007 Saturn Aura mid-size sedan, based on last year’s concept car of the same name. Uplevel models of the Aura will feature GM’s first application of a new six-speed automatic transmission mated with the 3.6L DOHC V6.
Later in the 2007 model year, Saturn will offer the Aura Green Line, a 2.4L Ecotec-based hybrid that will use a powertrain system similar to the Vue Green Line. (Earlier post.) It marks the first application of a hybrid powertrain in a production GM passenger car.
The non-hybrid Aura goes on sale late this summer in two trim levels: entry and uplevel. Saturn will offer two powertrains at launch: a standard entry-level 3.5L V6 with variable valve timing (VVT), and the uplevel 3.6L DOHC V6 with VVT.
The entry-level 3.5-liter engine generates 224 hp (167 kW) and 298 Nm of torque. The higher-end 3.6-liter engine is rated at 252 hp (188 kW) and 340 Nm of torque.
This latter engine is mated with the all new Hydra-Matic 6T70 six-speed automatic transmission, the first application of this in the GM Powertrain portfolio. The transmission allows for strong performance combined with strong fuel efficiency.
The Green Line hybrid system, as applied in the VUE, is based on a Belt Alternator Starter system—essentially what underlies a Start-Stop system—albeit one with some modifications that provide a small degree of traction assistance.
This system is GM’s third production hybrid system, the others being the high end two-mode hybrid system that GM will apply first in the Tahoe and Yukon full-size SUVs and the low end micro-hybrid applied in the Silverado Sierra.
Combined with other vehicle modifications to decrease fuel consumption, the Saturn VUE Green Line hybrid delivers an estimated 20% improvement in fuel economy.
GM has not yet announced the level of fuel savings to be delivered by the Aura Green Line hybrid implementation—but the automaker’s choice of a 2.4-liter Ecotec rather than the standard 3.5-liter V6 is an indication that GM may be trying to optimize fuel economy in the model over performance.