My relationship with the new fullsize GM hybrid SUVs continues to be a love/hate one. I love the fuel savings and cleaner emissions delivered by these “green beasts,” but I hate that consumers still cannot get one for less than 50 grand.
I also hate the acceleration/deceleration whine produced by the transmission/generator unit while operating in electric mode at low speeds.
The good news is, these new trucks see a 40 percent fuel economy improvement in city driving and a 25 percent rise in fuel economy on the highway thanks to the new two-mode hybrid powertrain.
The even better news is that GM is producing ALL of the new hybrid trucks right here in north Texas at the Arlington GM Assembly Plant.
On the outside, the new hybrid models closely resemble their gas-only production counterparts. The differences are that hybrid models receive a new front fascia (with taller air dam), new aluminum hood (for reduced weight), new rear fascia (including LED taillamps) and aluminum rear hatch (again for the weight savings). And, of course, the hybrid badging.
Inside we see the hybrid designation on the instrument panel, which includes a new “economy” gauge to alert drivers of their most fuel-efficient driving habits. There is also the hybrid mode display on the center dash monitor which shows energy use and production from the hybrid gasoline/electric motors.
This new “2-Mode hybrid” powertrain is a huge leap forward of the partial hybrid technology GM put into its light-duty pickups a couple of years back. Two-mode hybrid mates a Vortec 6.0-liter V-8 internal combustion engine with a 300-volt electric drive motor and unique automatic transmission, the latter of which operates in dual modes, thus giving the powertrain its name.
In the first mode, at low speed and light loads, the vehicle is capable of operating in any of three modes: electric only, gasoline-power with electric assist or gasoline engine only.
The second mode is used primarily at highway speeds where the gasoline engine combines with the electric assist for high load situations such as passing and towing/hauling.
The new hybrid SUVs also see the benefit of active fuel management technology in the internal combustion component of the powerplant. Active fuel management allows the V-8 gasoline engine to operate in four-cylinder mode under light loads.
The two-mode hybrid powertrain operates nearly seamlessly save for the added gauges and lights in front of you. About the only time you really “feel” that this is a hybrid system is when the gasoline engine shuts off at low speeds or at rest – and did I mention that whining noise?
Fullsize SUV fans will still enjoy the fact that the new hybrid models are built on the same GMT900 platform as their gasoline counterparts and are available in two- and four-wheel-drive. All of the standard safety equipment is still there and the third row seats are standard.
We recently tested the new 2009 Tahoe 4WD Hybrid rolling in new blue granite metallic paint. Also new for the 2009 model is OnStar 8.0 with Stolen Vehicle Slowdown technology and upgraded navigation features. Fuel economy rolls in at 20 mpg city and highway.
As I stated near the outset, pricing starts north of 50 large, and thanks to a couple of add-ons, our 4WD Tahoe Hybrid tester comes rolling in at a “green” $56,500.