2009 Cadillac Escalade HybridPosted on October 28th, 2008
Two-mode technology gives the Escalade fifty percent better fuel economy in city driving.
By Nina Russin
Last year General Motors rolled out two hybrid sport-utility vehicles, the Chevrolet Tahoe and GMC Yukon, utilizing technology developed jointly
with Chrysler and BMW. This year, the automaker unveils the Cadillac Escalade hybrid: the first full-sized luxury sport-utility vehicle to feature the two-mode system.
The new technology takes gasoline/electric powertrains to a new level by having separate methods of operation for low and high-speed driving. A nickel-metal hydride battery provides power to the electric motors that work in conjunction with a six-liter gasoline engine.
At start-up, the engine operates on all eight cylinders. After about three minutes, the catalytic converter in the exhaust system reaches operating temperature, and the on-board computer takes over.
Active fuel management cuts power to half of the engine cylinders when power demands are low. During city driving, the cars runs on electric power at idle and speeds under twenty-five miles-per-hour. The electric motors restart the gas engine when necessary, eliminating the need for a traditional starter motor.
Although the engine operates on eight cylinders during hard acceleration, electric motors provide enough power to keep the Escalade in four-cylinder mode most of the time. The hybrid’s city fuel economy is seven miles-per-gallon better than its gas-powered cousin.
On the highway, electric motors extend the intervals during which the car can run on four cylinders. The most amazing thing about the technology is its invisibility to the driver. Were it not for a display in the gauge cluster, the driver would be unaware of shifts between four and eight cylinder operation.
Electronic components save energy
General Motors followed Toyota’s lead, replacing the mechanical steering pump and air conditioning compressor with lighter, more efficient electric components. The electric air conditioning compressor can run independent of the gas engine, to prevent the car from heating up when it’s stopped at a traffic light.
The electric power steering pump is lighter than the hydraulic part it replaces. Since both the compressor and steering pump are self-contained units, they reduce parasitic power loss, improving the gas engine’s fuel economy by half a mile per gallon.
Hybrid powertrain improves low-end torque
Hybrids inevitably win the race out of the toll booth, because electric motors develop maximum torque at extremely low speeds. Getting seventy-five hundred pounds of sheet metal moving is no small feat: making it accelerate from zero-to-sixty miles-per-hour in under seven seconds deserves a standing ovation.
The Escalade is considerably heavier than the Chevrolet and GMC trucks that share the same hybrid technology, decreasing its overall fuel economy by about a mile per gallon in comparison. The additional weight is quite noticeable when cornering. When I took a decreasing radius turn at speed, I could feel the truck pull to the outside in the apex.
Regenerative braking recaptures heat produced by the brakes and uses it to recharge the 300-volt battery pack. The regenerative brakes are separate from the truck’s hydraulic brakes. According to GM engineers, they significantly increase brake pad life for the hydraulic components. They also make the car stop faster when it needs to: a boon for commuters who travel on busy urban roads.
The Escalade has an independent front suspension and link suspension in the rear to enhance its towing capability. The two-wheel drive platform tows up to 5800 pounds, while the four-wheel drive model tows up to 5600 pounds.
Real-time damping automatically adjusts the shocks to smooth out bumps in the road, giving the Escalade the seamless ride Cadillac is known for. Steering feedback is not as precise as it would be on a unibody car with high torsional rigidity, but there’s no excessive play either.
Visibility around the car is good: standard rear park assist sounds an audible alarm when the vehicle approaches obstacles to the back below the driver’s line of vision.
Although available four-wheel drive gives the Escalade enough traction to go off-road, it’s not the best choice for buyers who want to spend a lot of time on rugged trails. Twenty-two inch chromed aluminum wheels wouldn’t last long in the wilderness; nor would the optional running boards that deploy automatically when the doors open.
Seating for up to seven passengers
The Escalade’s plush interior is what one would expect from Cadillac: heated and ventilated first and second-row seats, a 5.1 surround-sound system with standard XM satellite radio, power sunroof, and tri-zone climate control.
There is enough room in the second row for three adults. The center console takes away a little legroom from the center passenger, but the average adult should be fine on a short ride. Both first and second-row passengers get overhead reading lamps. Four ceiling vents keep rear passengers comfortable in hot and cold weather.
Adjustable pedals and a power tilt steering wheel enable shorter drivers to find a safe, comfortable seating position. Redundant Bluetooth, audio and cruise control functions on the steering wheel minimize driver distraction.
A two-piece center console bin stows the headphones and remote for the DVD entertainment system up top, with a separate bin for DVDs below. Multiple 12-volt power points allow all three rows of passengers to recharge electronic devices on the go. There is also a 115-volt outlet in the cargo area.
The battery pack is located under the second-row seats. Though it has no effect on hip, head or legroom for the second-row passengers, the battery pack limits the manner in which the cargo floor can be configured.
Both second and third row seats fold flat using a single lever on the seat cushions. But they don’t create a flat load floor. There is plenty of room to load bicycles in back without removing the third row seats, but the car’s high liftover height and spaces between the seats make it awkward.
Buyers who plan to carry bikes on a regular basis will probably want to install a hitch mounted rack or roof rack. The Escalade comes standard with roof rails, and a rubber step pad on the rear bumper. Optional power running boards ($1095) make it easier for smaller drivers to reach a top rack from the sides.
The Escalade hybrid comes standard with front, side and side curtain airbags, antilock brakes, stability and traction control. A free one-year subscription to OnStar adds automatic police and EMT notification if the airbags deploy.
Hybrid components are warrantied for eight years or 100,000 miles. A four-year, bumper-to-bumper warranty covers all other components,
Base price for the Escalade Hybrid is $70,735, not including a $950 destination charge. Cadillac produces the Escalade at its assembly plant in Arlington, Texas.
Likes: Exceptional fuel efficiency for a full-sized sport-utility vehicle with no compromise in passenger comfort or performance. General Motors’ two mode system works so well that its operation is invisible to the driver.
Dislike: Folding the second and third-row seats flat does not create an uninterrupted cargo floor, making it more difficult to load large items in back.
Model: Escalade Hybrid 2WD
Base price: $70,735
As tested: $72,780
Horsepower: 403 Hp @ 5700 rpm
Torque: 417 lbs.-ft. @ 4400 rpm
Zero-to-sixty: 6.8 seconds
Antilock brakes: Standard
Side curtain airbags: Standard
First aid kit: N/A
Bicycle friendly: Yes
Fuel economy: 20/21 mpg city/highway
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