Articles & Reviews

The Best SUV Chevy Has Ever Built

Although 2006 is in its infancy, I recently spent the day driving Chevy's new 2007 Tahoe SUV. GM introduced the full-size rig to an assortment of auto journalists in none other than sunny Arizona; but if you think the plan was to simply drive the latest GM product down Scottsdale's cacti-lined Boulevards, guess again. Our route took us along a series of secondary highways that connected Lake Roosevelt to Tortilla Flats via the Apache Trail. As Terry Woychowski put it, Chevy's Chief Engineer for full-size trucks, "If we didn't have confidence in this vehicle, we wouldn't have tackled the Apache Trail," a dust-laden roller coaster of a dirt road that clings to canyon walls, dipping and diving hundreds of metres (900 feet) at a time. This former supply trail is characterized by blind hairpin turns, severe wash-boarding and steep inclines - the compilation of which push a vehicle's traction and handling capabilities to the max.

With interior craftsmanship and design beginning to fail the test of time, combined with exterior styling that was long in the tooth, there's little arguing that Chevy needed to pay some immediate attention to its full-size line of SUVs. To rectify the detractions, the bowtie division didn't just plaster on a new front grille and throw in a revised instrument panel. No, they pretty much re-did the Tahoe from rubber to roof. Most apparent to the eye is its tremendously clean sheet metal, which by the way has resulted in a remarkable 0.36 co-efficient of drag (CD) - that's equivalent to the sleek C4 generation of Corvette (1992-1996) incidentally. And of course the better the CD, the better the fuel economy. Plus, a slippery shape generates less atmospheric turbulence, translation: reduced wind noise. Anytime an auto manufacturer can move something roughly the shape of a breadbox down a highway without it producing wind noise equivalent to a category-5 hurricane, progress has been made.

In addition to silently slipping through the air, the Tahoe's new body shape encompasses a front track 760 mm (3-in) wider than last year's and a rear track wider by 254 mm (1 inch). In overall length, the Tahoe has grown by approximately 50 mm (2 inches). But it's not all about getting bigger; the ride height has been dropped by 127 mm (0.5 inches) on the two-wheel drive (2WD) version and 254 mm (1 inch) on the four-wheel drive (4WD) setup. This was done to ensure the Tahoe meets the highest government crash test ratings, but fear not off-roaders; the 4WD Tahoe retains its 229 mm (9 inches) of minimum ground clearance.

Space reduction also applies to exterior panel gapping, which for 2007 is slimmed to only 4-millimeters. A close examination of the Tahoe's body failed to reveal a single misalignment or inaccuracy. The portals in the Tahoe's exacting shell opened and closed with the requisite "whump" of a premium automobile and imparted a sense of solidity.

Visually, Chevy has applied their now familiar "horizontal" theme to the front-end treatment of the Tahoe. They have also incorporated a full front fascia into the nose design rather than a separate grille and bumper arrangement. The benefit is more than good looks. The seamless integration of the fascia into the fenders eliminates gaps, which can incite high-speed turbulence, which Chevy worked so diligently to eliminate. Aesthetically I find the results very appealing. In fact from every angle the Tahoe pleases. After pouring over its exterior, I directed my attention inward and was more than pleasantly surprised. There is no connection to last year's vehicle in the interior architecture of the 2007 - everything is new, switches included.

Most noticeable off-the-bat is a new instrument panel and dashboard residing approximately 6-inches lower and more forward than the 2006 dash. The design and layout of the new gauge package is outstanding, setting a new standard for Chevy and GM truck products. Not only is the layout symmetrical and engaging, it incorporates build quality vastly superior to anything previously found in full-size Chevy and GM SUVs. Hard plastic trim framing controls and gauges is gone in favour of modern, cohesive construction appearing more European than domestic.

Fit and finish in the new cabin is first rate and simply indistinguishable from the imports thanks to plenty of premium-touch surfaces and materials, combined with restrained but tasteful styling elements. The only deflection from a perfect bulls-eye is the presence of small buttons for controlling HVAC (heat, ventilation, air conditioning) functions. Their look is absolutely dynamite, however adjusting HVAC settings would be simpler and more straightforward if it had larger dials - such as the beauties assigned to headlight operation and GM's shift-on-the-fly 4WD.

Speaking of beauty, I was particularly smitten with the Tahoe's front seats; in fact I would be smitten with anything holding me so comfortably, human or otherwise. These perches are new, not holdovers from vehicles past. They provide vastly more thigh support than most seats and are infinitely adjustable. Their chair-like architecture netted an elevated driving position resulting in excellent forward and side visibility. My tester was equipped with second row captain's chairs that folded and tumbled forward to allow wide access to the Tahoe's third row split bench. Grasping a single lever manually initiates the folding and tumbling task, but even sweeter is a power option that performs this plebian chore. The driver can activate this process with the push of an overhead button, or it can be engaged via a button mounted next to each second row seat. Also optional for 2007 is a power-operated rear tailgate. Owning a full-size SUV has never been so easy - literally.

What's not easy about these behemoth vehicles is stomaching their fuel bills, oft the major criticism against the full-size SUV segment. The Chevy truck reps at the Tahoe's launch made a point of emphasizing the improved fuel economy of their fourth generation small block V8, which continues to displace 5.3 litres (325 cu in); the modifications to this venerable mill are sufficient alone to fill an entire review. It now pumps out 320-horsepower and 355 foot-pounds of deliciously smooth torque, but are you ready for this: it delivers better fuel economy in the big Tahoe than the V6 engine powering Ford's mid-size Explorer. And according to GM, it also out distances the V6 Kia Sorento with a litre of fuel.

U.S. EPA ratings give the 2007 Tahoe 2WD a fuel economy rating of 16 mpg city and 22 mpg highway (the equivalent of 14.7 and 10.7 L/100 km). The 4WD 2007 Tahoe is rated closely behind at 15 and 21 mpg respectively (the equivalent of 15.7 and 11.2 L/100 km). And as for the V6 Explorer, EPA assigns a rating of 15 and 21 mpg respectively (again, 15.7 and 11.2 L/100 km) for the 2WD version and 15 and 20 (15.7 and 11.8 L/100 km) in 4WD format. The Korean-built mid-size 2WD Sorento tips the scale at 16 and 21 respectively while its 4WD edition dips the balance beam at 15 and 20 mpg (14.7 and 11.8 L/100 km).

So how did Chevy beat the mid-size V6-powered SUVs at the fuel-economy game? Well, lots of engine tweaking and re-engineering along with the application of GM's Active Fuel Management (AFM) technology, formerly labeled Displacement on Demand (DoD). Similar to DaimlerChrysler's Multi-Displacement System (MDS), AFM deactivates a series of valves, shutting-down four of the engine's eight cylinders when power demands are minimal. Is it detectable during driving? Not at all, and that's the beauty of this technology. When there's no need to run all eight taps, four automatically turn off. But it's unlikely the driver will ever notice, even when pulling the Tahoe's maximum tow rating of 3,492 kg (7,700 lbs) - well at least downhill.

The mechanical benchmarks sought in the 2007 Tahoe not only included impressive fuel economy and sizable power output but also extraordinarily low levels of noise, vibration and harshness. Many steps have been taken, such as chassis strengthening and tuning, to reduce or eliminate such irritants, the effect being immediately detectable. Road noise and operational harshness is extremely well suppressed, making the Tahoe's cabin a serene, hushed environment while underway. If my forehead furled at all, it was due to slightly more engine noise than anticipated. GM's GenIV V8 produces a refined note, but slightly more audibly so than say the purposely subdued HEMI V8 powering the slightly smaller Jeep Commander.

Pairing the fuel-stingy but potent GenIV powerplant to GM's 4-speed Hydra-Matic 4L60 autobox formulated a strong, reliable, proven partnership in which gear changes were executed smoothly and appropriate to the engine's output, resulting in competent but not startling acceleration and passing performance. It should be said that that same Jeep Commander I just mentioned, as well as its Dodge Durango next of kin, plus the full-size Japanese SUVs, Nissan's Armada and Toyota's Sequoia, offer 5-speed automatics, most even with manual mode actuation, a step above the Tahoe's in specification at least, while the Explorer V8 fits in a class-leading 6-speed automatic.

If an engine with fewer cubic inches and less grunt is desired, Chevy will offer the 2007 Tahoe 2WD with a 4.8-litre (293 cu in) V8 capable of 290-horsepower and 290 foot-pounds of torque, but other than a lower initial cost, why? This engine will be the base unit powering the 2WD Tahoe.

Onto the Tahoe's more rigid chassis, Chevy has hung an independent coil-over shock setup at the front with a five-link solid axle and coil spring setup at the rear. I had an interesting conversation with GM's engineer responsible for the Tahoe's suspension design and calibration, Brad Cwycyshyn, in which we explored the difficulty in finding the utopian balance of a smooth ride while maintaining sharp handling characteristics and control off-road. It was his view that suspension characteristics shouldn't be all about handling to the absence of ride attributes. He explained how painstakingly he and his team worked on the Tahoe's suspension calibration and geometry to strike the right balance between handling and comfort; after a challenging day of washboard and backroads, I think Brad and company have nailed it.

Although some expected oversteer crept in, the 2007 Tahoe remained remarkably stable over the most severe washboarding, sharpest turns and steepest inclines the Apache Trail could dish out. The vibration induced by the deteriorating dirt road highlighted the solidity of the Tahoe's body structure and its underpinnings. The vehicle absorbed relentless surface degradation without transmitting excessive jostling or harshness to the cabin, which remained rattle-free throughout. On the highway the 2007 Tahoe rides more like a premium sedan than a 4WD SUV, helping make long stints behind the wheel that much more enjoyable.

Along the way, it came time to test the 4-wheel antilock disc brakes that are affixed as standard equipment. A full-on stomp invoked considerable nosedive but ratcheted the Tahoe down from south of 100 km/h (62 mph) to nil in a manner more befitting a sports car. I was quite astonished with just how quickly and securely the 4WD Tahoe's substantial curb weight of 2,512 kg (5,537 lbs) was brought to a halt. Capitalizing on the SUV's powerful brakes is GM's StabiliTrak stability control system with roll-over mitigation technology.

Chevy provides this important safety technology as standard Tahoe equipment along with dual-stage frontal airbags. Optional airbags include roof-mounted side-curtain airbags providing protection at all outboard seating positions. In addition to deploying in the event of a side impact, these "smart" bags deploy when a roll over is imminent. A special sensor monitors the vehicle's acceleration and roll rates, triggering the roof-mounted airbags when a roll over is detected.

Because roll over incidents generally last longer than typical side impact crashes, the roof-mounted airbags remain inflated longer than conventional side impact airbags, and given the precarious trail our GM reps led us down, I couldn't be more happy with that knowledge. Knowing that GM has also included the sixth generation of OnStar communications as standard equipment didn't hurt either. In the event of an airbag deployment, it automatically notifies an OnStar advisor of the occurrence and the vehicle's location in order that rescue service response times can be enhanced.

And enhancement applies to almost every aspect of the 2007 Tahoe, regardless of whether a 2WD or 4WD version answers the key fob's call. Chevy has tied familiar parlance to the Tahoe's three trim levels, which begin with LS and ascend to LT before peaking at LTZ. Along the way, look for the usual content increments and some that are less usual, such as remote vehicle starting, first and second-row heated seats, Ultrasonic rear parking assist with a rearview camera system, power articulating running boards (mid-year availability), just like the Lincoln Navigator, and a rear seat 8-inch DVD screen with improved features. Topping my chart of convenience features isn't the power-operated fold and tumble second row seats, but rather the 60/40 split third row bench seat that not only folds down, but can easily be removed one segment at a time. And should more seats instead of less be a family need, the 2007 Tahoe can be ordered with seating for nine.

With family needs covered, lest we forget the needs of Chevy's core off-roaders? Chevy will soon offer a Z71 off-road package for those seeking higher ground. The contents of the Z71 package will include a specifically designed three-piece fascia with a protective, platinum skid plate, larger tow hook openings, larger fog lamps, 18-inch wheels in place of the base 17-inch'ers, and a more aggressive looking grille. And if the 18-inch wheels don't float your boat, optional 20-inch rollers are available. If this assortment of upgrades fails to project enough personality, a total of nine exterior colours should.

Whether the 2007 Tahoe is gleaming in Bermuda Blue or Gold Mist Metallic, it will undoubtedly impress. GM has done an outstanding job of moving the Tahoe, and eventually it's full-size cousins, into a completely new realm, positioning it to do head-to-head battle with premium, upscale SUVs from European and Asian shores.

"Chevrolet introduced the SUV with the 1935 Suburban, and the new Tahoe is the culmination of more than 70 years of experience building these vehicles," said Chevy General Manager Ed Peper. "The 2007 is not only the most refined SUV in the segment, we believe it to be the best SUV we've ever built."

Personally I wouldn't go so far as to concur with Peper in describing the 2007 Tahoe as the most refined in the segment - the Jeep Commander is a heck of a contender in that field and some of the Japanese do a good job too - but I would endorse his claim that it is the best SUV Chevy has ever built.

Specifications (4WD LT):

• Price Range (MSRP): TBA
• Body Type: 5-door body on frame SUV
• Layout: front engine, AWD / 4WD
• Base Engine: 290 hp, 290 lb-ft of torque, 4.8L, OHV V8
• Optional Engine: 320 hp, 340 lb-ft of torque, 5.3L, OHV V8
• Transmission: 4-speed auto
• Brakes (front/rear): disc/disc, ABS
• Curb Weight: 2,512 kg (5,537 lbs)
• Seating Capacity: 7 - 9
• Cargo Cap (max): 3,084 L (108.9 cu ft)
• Ground Clearance: 229 mm (9.0 in)
• Towing Capacity (max): 3,492 kg (7,700 lbs)
• Fuel Economy (5.3L 4WD city/hwy): 15.6 / 11.2 litres per 100 kilometres 
• Warranty (mo/km): 36/60,000 comprehensive
• Direct Competitors: Acura MDX, Buick Rainier, Cadillac Escalade, Chevy Trailblazer, Dodge Durango, GMC Yukon, Ford Explorer/Expedition/Excursion, Hummer H2, Infiniti QX56, Lexus GX 470/LX 470, Lincoln Navigator, Jeep Commander, Land Rover LR3/Range Rover, Mercedes-Benz ML350/500, Mitsubishi Montero, Nissan Pathfinder/Armada, Toyota 4Runner/Sequoia/Land Cruiser, Volkswagen Touareg, Volvo XC90
• Web Site: www.gmcanada.com