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The Car Connection
by Bob Hall

TORTILLA FLAT, Ariz. - It's not easy to get here, especially if you're coming from the Roosevelt Dam, some 22 miles to the northwest. Your only choice of "road" is Arizona State Highway 88, commonly known as Apache Trail. It's narrow ribbon of sand, dirt, loose stones, and gravel that torturously winds its way up and down steep canyon walls - often without even a hint of a guardrail - hugging those elevations with dozens of blind curves and narrow passages.

Normally this wouldn't be an ideal showcase for an "Ultimate Driving Machine" - but then the X3 SAV (Sports Activity Vehicle) isn't your normal BMW. A slightly smaller (yet larger inside) version of BMW's extremely successful X5, "the X3 will probably bring us more new customers than any other vehicle," predicted Tom Purves, BMW North America's CEO. He reminded journalists that many of them had criticized BMW "for being late to the SUV party. But it took awhile to develop the ultimate driving utility vehicle," he said, referring to the X5. "Now we're filling in the niches in our market penetration in a way we haven't since the X5's introduction."

xDrive and Apaches

Like the just-introduced 2004 version of the X5, X3 gets BMW's new xDrive all-wheel-drive and traction system. Using a transfer case located behind the transmission, xDrive varies torque between the axles and works in conjunction with BMW's Dynamic Stability Control (DSC) that incorporates traction control. In normal conditions, the torque split is 40-percent front/60-percent rear. (A split between 35/65 and 40/60 is considered optimum for traction and handling.) It's in the less-than-perfect traction scenarios (rain, snow, sand, gravel et al) where xDrive proves its mettle.

Receiving inputs from the DSC's sensors, xDrive factors the rotational speed of each wheel, steering angle, brake use, yaw and lateral acceleration, and then seamlessly alters the distribution of torque according to the situation at that second. Most extreme real world example: if both rear wheels are on ice, almost 100 percent transfers to the front axle. The actual transfer is via a multi-disc clutch that can be completely open, completely engaged, or engaged at any level in between. That's why the torque transfer is seamless, or in BMW parlance, "steplessly variable." "Think of xDrive as controlled transmission of torque," said xDrive Product Manager Bert Holland. "One-tenth of a second is all it takes, even in the most severe circumstances."

There was no ice along Apache Trail, just lots of washboard surfaces, some exposed, some hiding under the sand, truly a test for any all-wheel- or four-wheel-drive system. The X3 had little difficulty negotiating the Apache Trail, for xDrive (figuratively) shone as brilliantly as the Arizona sun did on the spectacular desert landscapes all around. As important as transferring available torque is, it won't solve all traction challenges. For those times when you "exceed the system," the DSC/traction control will intervene to either reduce engine torque and/or apply braking to the appropriate wheel.

On a number of sharp curves (where there was sufficient runoff area), we purposely exceeded the system by not slowing from our 20-plus-mph speed. Once the X3 went far enough into a right-hand curve where DSC judged our speed excessive, it gently applied the left rear brake and we just steered our way onto the next portion of the trail.

Training the power

Our X3 at that moment was the 3.0-liter six-cylinder (225-horsepower/214 pound-feet of torque) variant with the standard six-speed manual transmission (which we kept mostly in second gear) and optional sports suspension. Those driving X3s with the optional five-speed Steptronic automatic but no sports suspension seemed equally impressed with their Apache Trail experience. Later on paved, but still challenging roads, we drove one of those X3s and felt the non-sports suspension vehicle felt practically as good.

The X3 2.5i comes standard with BMW's 2.5-liter in-line six that produces 184 hp and 175 lb-ft of torque and starts at $30,995; the X3 3.0i begins at $36,995. The automatic adds $1275 and as with most BMWs there are a variety of option packages and stand-alone options that can kick the price up considerably. Besides the above-mentioned sports suspension, the $1500 Sport Package gives you more supportive "Sport seats," fancier wheels with 18-inch tires, a "sport" steering wheel and Shadowline (black) exterior trim. The extensive Premium Package is $3800 on the 2.5i and $3300 on the 3.0i, for on the 2.5i some of the 3.0i's standard features are included. A major component is the huge Panoramic Moonroof that consists of two large panels, both of which can be tilted up at the rear. The forward panel is largest and slides open. In total there's nearly ten square feet of glass area.

Three important things that aren't options are X3's rigid unitized body, its own version of BMW's double-pivot, strut-type front suspension, and superb engine-speed-sensitive rack and pinion steering. Servotronic vehicle-speed-sensitive steering is a $250 stand-alone option. X3's "Central Link" rear suspension is a new, beefed-up multi-link setup derived from 3-Series cars. It rides in a four-mount rear subframe designed specifically to reduce noise. Bottom line: the X3 definitely is a BMW through and through. There are no comprises in ride quality, NVH, steering, or handling. Plus the front driveshaft extends through the oil sump to give X3 a lower center of gravity than you'd expect.

Also unexpected is X3's 71 cubic feet of cargo volume (space behind the front seats) vs. X5's 69. (In total interior volume, X5 measures 97.6 cubic feet, vs. X3's 96.1.) Overall, X5 is larger, but not by much: 9/10-inch in wheelbase; 4.0 inches in overall length; 0.7 inches in width and 1.5 inches in height. More dramatic is X5's weight difference, over 600 pounds more than X3. BMW says that difference signals the vehicles' respective places in its model lineup, as does no V-8 power option for X3.

Compared to both BMWs, Jeep's Grand Cherokee is shorter in wheelbase and width; taller; between the two in overall length and weight; and measures 71.7 cubic feet of cargo volume. Also of interest, Grand Cherokee's co-efficient of drag (cd) is 0.45, the X5's is 0.38, 0.36 or 0.35 depending of model, and both X3s rate .35. That figure certainly helps X3's EPA fuel economy ratings: 18 city/25 highway for the 2.5i with manual transmission, 18/24 with automatic. The 3.0i delivers 17/25 manual and 16/23 automatic.

Perhaps the most important thing the X3 delivers is its BMW-ness. Inside it looks like a BMW with switchgear and trim that will be familiar to any BMW-phile. Its composure on the road, its right-on steering, its firm ride and agile handling, all remind you this is a BMW. You're not thinking, "this is an SUV," (or even an SAV).

I think that's the reason behind Tom Purves' comment about X3 bringing BMW new customers. It drives like a real BMW, has SUV carrying capabilities along with superior traction, and is way more affordable than big brother X5. This one's tough to beat.

2004 BMW X3
Base price: $30,995 (X3 2.5i); $36,995 (X3 3.0i)
Engine: 2.5-liter in-line six, 184 hp/175 lb-ft (2.5i); 3.0-liter in-line six, 225 hp/214 lb-ft (3.0i)
Transmission: Six-speed manual (standard), five-speed automatic optional, xDrive automatic all-wheel-drive system
Length x width x height: 179.7 x 73.0 x 66.0 in
Wheelbase: 110.1 in
Curb weight: 4993 lb (manual 2.5i), 5049 lb (automatic 2.5i and 3.0i manual); 5104 lb (automatic 3.0i)
EPA City/Hwy : 18/25 (manual 2.5i), 18/24 (automatic 2.5i); 17/25 (manual 2.5i), 16/23 (automatic 3.0i)
Safety equipment: Dual-stage front airbags, front seat side-impact airbags, four-wheel disc brakes, four-wheel ventilated disc brakes, Dynamic Stability Control including electronic brake proportioning, ABS, Dynamic Brake Control, Hill Descent Control & cornering/braking stability enhancement
Major standard equipment: AM/FM/CD audio system with ten speakers including two sub-woofers, Sensatec leatherette upholstery; power windows, locks, remote keyless entry; (both) automatic climate control, power seats, cruise control (3.0i)
Warranty: Four years/50,000 miles, plus "full maintenance program"

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