The Nissan Xterra is built on a truck chassis. Its body is attached to a boxed-in steel ladder frame and uses a rugged suspension, double-wishbone front and solid axle with leaf springs in rear. It's the same chassis as the Nissan Frontier pickup truck, although the Xterra has a higher center of gravity that you can feel in the ride, which is reasonably comfortable thanks to a longish wheelbase.

During our week in the Nissan Xterra, including 40 miles on gravel and dirt roads, we didn't encounter any harsh spots in the ride, which is saying a lot, although the side-to-side motion is a bit more pronounced than with crossovers.

We took a few runs on a rough off-road course, and the Xterra met every traction and crevice challenge it faced, using 4WD HI and 4WD LO, easily switchable with one knob on the dash. Also, with short overhangs front and rear, things don't easily drag in the gulleys. You can take it hunting or dirt biking to the top of rugged mountains with no worries.

We tested Hill Descent Control on the off-road course as well. HDC only comes on the Off-Road model with automatic transmission. Hill Descent Control allows you to travel down a steep hill and rely on electronics (raising both feet off the pedals) to keep the Xterra safe and steady at 5 mph, with throttle control and ABS applied by the truck's tiny brain and feet, better in this circumstance than your own big ones. If you live in a place that has snowy and icy hills in winter, HDC, available on some other SUVs (that don't have to be off-road equipped), could save your life or the life of another, for example a passenger on the sidewalk. It helps the driver keep the rear from sliding out on a steep, muddy descent, so you don't slowly slide off the trail and into a tree.

Hill Start Assist comes on the Xterra Off-Road with automatic transmission, though that seems strangely misplaced. Hill Start Assist allows you to start moving forward on a steep uphill, without drifting back, useful off road and in San Francisco. But with an automatic transmission, that's not a problem, because you have two feet and there are only two pedals. It's needed with the manual transmission Xterra, if anything, but Nissan didn't design HSA to work on that one.

The 4.0-liter V6 that's used in the Xterra is a great engine, a stroked version of the award-winning 3.5-liter that's used in the 350Z sports car and other Nissans. It has all the right stuff: aluminum block and heads, Teflon-coated pistons, Continuous Valve Timing Control (CVTCS), Nissan variable Induction Control System (NICS), silent timing chain and microfinished camshaft and crankshaft surfaces, digital knock control system, and 105,000-mile spark plugs.

Fuel economy for the Nissan Xterra is an EPA-estimated 15 city and 20 highway miles per gallon with 4WD, a bit more with 2WD. It would get more, if the body wasn't such a brick.

The engine certainly has plenty of horsepower and torque, 261 hp and 281 pound-feet, but its torque curve, peaking at a high 4,000 rpm, is more suited to a sports car than a truck. As a result, the automatic transmission kicks down a lot at casual speeds, even 35 mph, from fifth gear to fourth; but because it's so smooth, you hardly notice it. However you do notice that the Nissan Xterra doesn't feel terribly powerful. Until you boot it, and then it blows you away. When you let it run, you find yourself driving a truck SUV that wants to be a . There will be no problem passing on two-lanes, or running with the hot sedans up long freeway slopes.