Reverence Due for an Economical Hybrid SUV

"I can't believe this!" said my sister, who had taken over driving duties midway along the New Jersey Turnpike. "We're home. We didn't stop for gas. And we still have a half of tank? Wow!"

Wow, indeed.

The two-mode hybrid is engineered to produce the best fuel efficiency under all driving conditions without sacrificing any of the qualities that attract people to big SUVs in the first place. As its name implies, it essentially does this two ways:

In Mode 1, at low speeds or with the Tahoe carrying light loads, the Tahoe can operate electrically with its 300-volt battery powering electric drive motors; or it can run on gasoline-engine power only, or any combination of engine and electric power.

Mode 2 is for highway driving, where some electrical assistance still is given to the engine, but also is where what GM calls Active Fuel Management comes into play. AFM deactivates four of the V-8 engine's cylinders if the SUV's computer-controlled transmission "thinks" the Tahoe can continue running at a given speed with a given load using less power. The result is fuel saved in a big vehicle that once consumed it at the rate of 10.5 miles per gallon in the city and barely 17 mpg on the highway.

That's progress.

ON WHEELS WITH WARREN BROWN Listen from noon to 1 p.m. Tuesdays on WMET World Radio (1160 AM) or http://www.wmet1160.com.