Chevrolet Tahoe Hybrid — spend on technology save at the pump

By Jim Meachen and Ted Biederman

We think improving fuel economy — even just a mile per gallon — is a good thing. So we were intrigued when we first got word that General Motors was developing a full hybrid system for its large truck-based sport utility vehicles that delivers in the neighborhood of 25 percent better fuel economy. Then in the fall of 2007 we got to drive a prototype Chevrolet Tahoe Hybrid for a few miles and we were impressed.

Now that we've spent an additional two weeks with the hybrid — we are no less impressed with its seamless nature from performance to overall handling and braking. It's basically a no-compromise Tahoe.

When you consider that the hybrid in two-wheel drive configuration is rated at 21 mpg city and 22 highway compared to 14/20 for the standard edition, the hybrid advantage is obvious. Mileage for the four-wheel drive hybrid is 20/20 compared to 14/19 for the standard 5.3-liter V-8.

If you are now chuckling over the perceived absurdity of a hybrid in a three-ton vehicle, consider this. Driving 15,000 miles a year under normal city/highway conditions, the Tahoe Hybrid can save between 150 and 200 gallons of gas a year. If more than 75 percent of your driving is done in the city or in crawling stop-and-go freeway traffic, it's not out of the question to save as much as 300 gallons as pointed out by the high city numbers.

At $3 a gallon that represents a savings up to $900 a year. But only the most optimistic person believes that gas will be sold on average over the next five years at $3.

Here's the bottom line — automotive writers who have spent considerable time in the two-wheel drive hybrid with its 6.0-liter V-8 realized between 19.5 and 20 miles to the gallon while averaging about 16 mpg in the 5.3-liter gas engine.

Perhaps economics more than environmental correctness will dictate the purchase of a Tahoe Hybrid. But the bottom line is that the hybrid driver will sacrifice nothing in the driving experience.

What he will sacrifice are some greenbacks at the time of purchase. We figure the hybrid is running about $6,000 more than a comparably equipped gasoline-only Tahoe with the popular 5.3-liter V-8. We must note that there's a difference of opinion on initial cost among writers ranging from $5,000 to $8,000.

Is it worth it? There's a tax credit available with the Tahoe. Take that amount — it could be as much as $3,000 (check the IRS Web site) — off the purchase price and then based on your driving history figure your savings at the pump. With gas prices fluctuating like never before, it would not be out of the question to break even in three-to-five years.

So what do we mean by a full hybrid? Simply put, it means that the vehicle can run strictly on electrical power at slower speeds. GM claims that the Tahoe, and its sibling the GMC Yukon Hybrid, can reach 32 miles per hour before the gas engine cuts on.

In a discussion with GM executive Bob Lutz in the fall of 2007, he bragged how he could creep the short distance between his home and the country club in a Tahoe Hybrid without the gas engine coming on.

Nice story, but realistically most of the fuel savings will come while sitting at a stoplight or mired in traffic with the gas engine cut off or by easing away on a green light keeping the gas engine at rest until 4 or 5 miles per hour. Beyond that, the need for speed overcomes the concern over gas mileage.

The new hybrid system, developed jointly by GM, BMW and Chrysler, is called "Two Mode." It features two sizable 60-kilowatt electric motors packaged within what GM calls an electric variable transmission (EVT).

EVT is like having two transmissions inside one, a continuously variable drive for light loads and the equivalent of a four-speed fixed-ratio automatic for high load conditions.
Like other hybrids, the Two Mode has a battery pack for storing electricity, regenerative braking to capture energy and the ability to shut off the engine when the vehicle is stopped.

The Tahoe is propelled by GM's 6.0-liter V-8 with cylinder-deactivation technology, meaning that in cruising situations the engine will run on just four cylinders. The big V-8 develops a solid 332 horsepower insuring that it has performance equal to the 5.3-liter V-8. Measured in terms of 0-to-60 starts it's about 8 seconds.

The only sacrifice is in towing capacity. The standard Tahoe can tow up to 7,700 pounds. The hybrid's capacity is 6,000 pounds. But that's still a lot of towing power and we don't see this as a drawback in very many cases.

Like the regular Tahoe, maximum cargo volume is a good 109 cubic feet and there’s a healthy 60.3 cubic feet behind the second-row seats. Space behind the optional third row of seats is a very useable 16.9 cubic feet. Note that the third row does not fold flat into the floor as in some trucks including the Ford Expedition, but they do fold down and they can be removed in two sections each weighing about 65 pounds. Our test trucks had second row captain’s chairs that could be powered down and then up against the front seats with the push of a button.

The dashboard is stylish with good use of quality plastics and excellent faux wood trim. Gauges are easy to read and the wide range of read-outs and settings are easily assessable. We think the interior setup is a good as any in the segment. A Huge center bin will hold a purse, small laptop or a camera bag.

The rear-wheel drive version starts well equipped at $51,405 including destination charge. The four-wheel drive hybrid begins at $52,210. Edmunds.com's True Market Value predicts customers can save between $3,000 and $4,000 on the purchase price.
Our rear-wheel drive test vehicle included a power sliding sunroof and rear-seat entertainment bringing the bottom line to $53,695.

Chevrolet has decided to outfit the hybrid with several items such as navigation and premium audio that are optional equipment on non-hybrid models.

We advocate buying the most economical vehicle that will meet your needs. And it most cases it doesn't have to be a big truck. But if you need a big truck-based sport utility for towing, crawling off road or hauling six or seven passengers on a regular basis, this may be the way to go.

Essentials:
Base price: $51,405; as driven, $53,695
Engine: 6.0-liter V-8/electric assist
Horsepower: 332 @ 5,100 rpm
Torque: 367 foot-pounds @ 4,100 rpm
Transmission: CVT plus 4-speed automatic
Drive: rear wheel
Seating: 2/2/3
Wheelbase: 116 inches
Length: 202 inches
Curb weight: 5,617 pounds
Turning circle: 39 feet
Towing capacity: 6,000 pounds
Luggage capacity: 16.9 cubic feet
Maximum cargo capacity: 109 cubic feet
Fuel capacity: 24.5 gallons (regular)
EPA rating: 22 mpg highway, 21 city
0-60: 8.2 seconds (Road & Track)
Also consider: GMC Yukon Hybrid, Toyota Highlander Hybrid

The Good:
• Fuel economy advantage over regular Tahoe
• Stylish cabin with quality materials
• Performance on a par with gas Tahoe

The Bad:
• Third-row seats do not fold flat

The Ugly:
• Price premium for hybrid may be too much to overcome