Driving Impressions

By June 11, 2009

The Tahoe rides quite well for a big, heavy utility and drives much less like a truck than its predecessor. We won't say it drives like a car, at least any car less than 10 years old because those have also advanced.

The Tahoe uses independent front suspension and five-link rear suspension with coil springs at both ends. There is noticeable body roll, some pitching on frost heaved interstates and nose-dive under heavy braking, but these characteristics are expected in a truck and do a good job of communicating how hard you're pushing it while maintaining stability. Multiple suspension tunes are offered, with a smooth ride setup standard on most, Autoride providing real-time damping and self-leveling rear on the LTZ, and the Z71 package for off-road use. The Z71 is firm and set-up more towards speed over rough terrain than softness for ultimate articulation, and the Autoride proves useful on variable road surfaces or towing; do remember automatic leveling on the truck is not a substitute for a proper weight-distributing hitch.

We prefer the smaller-diameter wheels over the 20-inch wheels. The ride was comfortable but not at all soft or spongy with the taller tires on the 17-inch wheels, and a truck with 20s got us along a winding road only slightly faster than 18s and that difference is easily attributed to the 20-icnh tire being more performance oriented. The 20-inch wheels might look nice, but they come with tires with nearly three inches less sidewall area and thus provide much less cushion for absorbing bumps along the way. We recommend you try the 20s before you buy.

The Tahoe's steering is among the best in big, truck-based utilities, nicely weighted and void of free play and any wander. Three-ton trucks more than six feet tall don't change direction like cars and if you approach a corner too fast the Tahoe understeers and scrubs off speed; the predictability and consistency are ideal for the average Tahoe driver.

The base model 4.8-liter is a capable, smooth engine that requires some revs to make its power. Upgrading to a 5.3-liter adds about 25 hp and 35 lb-ft of torque, but more importantly it adds 50 percent more gears with a six-speed automatic, so it handily accelerates and tows better with no loss in fuel economy.

A 5.3-liter and six-speed automatic are plenty for a Tahoe, and the six-speed lets the engine use its four-cylinder mode a bit more than before; it takes fuel to make power and move the Tahoe down the road, regardless of the number of cylinders being used. You can't tell the difference between the 310 and 320-hp versions of the 5.3 but the aluminum-block does take a few pounds off the front end.

The transmission will make the right gear decisions with less reluctance to downshift than the old four-speed auto, and it has a tow-/haul mode for use pulling a substantial trailer. It also offers a manual mode via a shift button on the stalk but you must first move the lever to the M position. Engaging tow/haul mode changes the one-touch lane-change signal from three blinks to six, a useful feature.

Maximum tow capacity is listed at 8400 pounds (8200 on 2WD) but that's assuming you go alone in an empty truck. If you plan on bringing friends, gear and any trailer more than 6500 pounds, we recommend checking into a Suburban.

Tahoe LTZ may be equipped with a 6.2-liter V8 of 395 hp and 417 lb-ft of torque. This is a slightly detuned (down 8 hp) version of the engine used in the Yukon Denali, Cadillac Escalade and some GM half-ton Crew Cabs. Typically lux adds weight so the LTZ 6.2 should be the quickest GM full-size SUV, and unlike Denali and Escalade the LTZ offers low-range 4WD.

It sounds oxymoronic but driving the Tahoe Hybrid is both different and the same. You don't do anything different to drive it, and the gas-electric drive system controls everything automatically. Turning the key always switches it on but doesn't always start the gas engine like you're used to; that happens more often at temperature extremes and ours more when we chose Reverse than when we went to Drive.

At very low speeds in the Hybrid propulsion is by electric power only, and you have to watch for people walking out in front of you in parking lots since there is only tire noise. The system will do 30 mph on electric alone in ideal circumstances but in most cases the gas engine is on by 10 mph. It usually shuts off the gas engine when the vehicle is stationary and the majority of time your foot is on the gas pedal it is a combination of the gas engine and electric motors powering you.

If you step on the gas hard as you might to get across a busy street there is a moment, some fraction of a second, before the gas engine starts and the system delivers its full 367 lb-ft of torque, so you should try that in the open a couple of times to know exactly how the truck will respond. There's enough power to get the Hybrid (and a 4000-6000 pound trailer) going easily, though it may sound odd at first as the gas engine goes to a certain rpm and stays there while the truck catches up with it.

The hybrid system uses an Atkinson-cycle 6-liter V8 engine and dual electric motor/generators inside a transmission with four conventional gears because in certain high-load conditions those are the most efficient; the 300-volt battery pack is beneath the second-row seat so it uses no cargo space.

That battery pack is charged by the motor/generators when the gas engine runs and when you are moving with your foot off the gas, such as descents and approaching stop signs. Energy that would normally be turned into heat by the brakes is used to recharge the battery pack which is why the Hybrid's fuel economy advantage is primarily in the city.

Although the nav-screen display shows the battery being charged when your foot's off the gas, the economy gauge does swing to the charge side until the brake pedal is pressed, and it doesn't go far right until the pedal is pressed hard. This makes the brake pedal a bit touchy in maneuvering and makes most drivers stop with more lurch because energy being recaptured for charging decreases with speed so the brakes have to take over. This is typical behavior of hybrids and practice will eventually smooth things but it's difficult to match a non-hybrid Tahoe for braking smoothness.

We found that manually downshifting to control speed on long descents did not appreciably increase the charge rate like we expected it to; gas engine compression helped but needing the brakes at all surprised us. The battery could have been at full charge (unlikely after the climb up the hill) but we never noticed battery charge level on the screen. We also found that if you got on the brakes hard there was a momentary delay before the needle-swing to heavy charge rate so the brakes stank at the bottom of a tight, winding hill. In comparison, a standard gas-engine Tahoe where we could use the tap shifter and extra gears for ideal control didn't have smelly brakes at the bottom of the hill.

We don't think the standard Tahoe's 250-pound weight advantage over the Hybrid made the difference there, but it probably played some part in the Hybrid feeling a bit more ponderous than the standard Tahoe. The Hybrid's low rolling resistance tires didn't handle any less competently than other same-size all-purpose tires, although they feel like 20s on some sharp, small impacts (like lane-divider Bots dots) and we suspect they run higher pressure than the standard Tahoe. The hybrid uses a 42-volt motor to drive the steering pump and while steering feel is as good as regular Tahoe we like that this keeps up better in repeated maneuvering like trail rides or backing a trailer and that the Hybrid's engine compartment is very clean and uncluttered.

On level urban highways our 4WD Hybrid's trip computer showed 20.3 mpg, around town without any gridlock or jams, it showed 16.5, and in a mixed, relaxed drive it recorded 19.8 mpg (the gas pump and GPS backed up these numbers). When we drove a similarly-lux non-hybrid 5.3-liter with the six-speed automatic in the same places, conditions, speeds and times, it bettered the Hybrid on the highway at 21.2 mpg, did 13.3 around town and the mixed route at 17.7.

The Hybrid is ideal for people who spend all week plodding around in a city but take the family and a 4500-pound trailer out on a weekend. Without the city use the XFE or standard Tahoe will serve as well, and if you don't tow a trailer a minivan or larger crossover will have more room, drive more comfortably, offer the higher seating position, be just as safe, and get better mileage. Given our test results and the fact that the Hybrid has a slightly smaller fuel tank, long-distance cruising range might be better on a non-Hybrid.

Since our nearest E85 station needs most of a fuel tank to make a round trip to we did not have an opportunity to test on E85. We've found no reason to doubt the 25-percent decrease in mileage reflected in EPA figures and expect performance to be at least as good as the gasoline engines.