New Tahoe Hybrid
2008 Chevrolet Tahoe Hybrid still offers the same SUV quality with a better fuel efficiency. Chevrolet’s two-mode hybrid system was developed together with BMW and DaimlerChrysler.
Installing the hybrid powertrain meant giving the Tahoe a distinctive look. Since the system adds on around 400 pounds of curb weight, GM engineers had to remove some mass from other places. Aluminum replaces steel at the rear lift-gate, hood and bumper. An all-new stamping of the hood ties into modified front-end features to increase aerodynamic slip. Even the running boards have been redesigned to help the Tahoe slide thorough the air with less effort. Further mass was extracted from the seats, wheels and tires.
The usual engine-driven accessories have been replaced by all-electric versions, so power steering and AC work while the Tahoe is running in both electric-only and autostop mode. Reports say that the core hybrid technology behind the two-mode transmission had been tested in the running gear of GM-Allison public transit buses before being incorporated into the larger GM hybrid plan.
Cramming hybrid technology into the existing Tahoe body without having to tear up the base platform or the Arlington, Texas plant where the Tahoe will be built has helped streamline production. GM expects to have the two-mode system installed in showroom Tahoes and Yukons available this Fall as 2008 models. GM says the system improves city mileage by 40 percent. GM’s has yet to reveal highway improvement figures, though had said the composite highway target was 25 percent. Engineers say they’re hoping to best that highway figure when the official numbers are released.
Channeling the power according to driver demand is the HOS, or Hybrid Operating System. By joining the HOS and two-mode transmission with existing engines, GM plans to make hybrid technology across the entire model lineup. Theoretically there are no limitations as to which engines can bolt up to the two-mode transmission, from full size trucks to smaller Saturns. A turbodiesel or even flex-fuel engine could be incorporated to the transmission, with the HOS sorting it all out.