BMW X3 sport activity vehicles put the power to every wheel
Bob Plunkett, Sat, 26 May 2012 06:30:18 PDT
TORTILLA FLAT, Ariz. -- To reach Tortilla Flat, a sand-scratched oasis in Arizona's Superstition Mountains, we follow the Apache Trail, a narrow ribbon of sand and stone cut against red-rock canyon walls with twisty cutbacks pitched on the brink of sheer cliffs and no guard rails.
For navigating such a treacherous route, not just any vehicle will do -- you need a rig with traction applied at every wheel to keep tires tracking through all that gravel.
Our trek on the Apache Trail becomes a safe -- even fun -- run with complete traction confidence generated from the sure-footed nature of a 2012 X3 xDrive3.5i sport utility vehicle from Germany's Bayerische Motoren Werke -- that's BMW to you and me.
To emphasize X3's utility and wily traction manners, BMW nixes the SUV acronym in favor of the three-letter descriptive of SAV, meaning sport activity vehicle.
Think of it as a raucous sports car yet rigged with the boxy utility bay of a wagon.
We see the X3 as resembling one of BMW's 3-Series sports sedans, only it's jacked up in suspension and carries a SUV's cargo compartment.
The boxy package measures 15.25 feet long by 6.175 feet wide and stands 5.45 feet high at the roof.
That makes it only slightly smaller than BMW's mid-size X5 wagon, in a manner similar to the way BMW's mid-size 5-Series and compact-class 3-Series sedans compare in step-down size progression.
A forceful in-line six-cylinder engine fits in front of the four-door passenger compartment that comprises two rows of seats for five riders plus a cargo bay at the rear accessible through a top-hinged tailgate.
Actually, BMW makes two versions of the X3, one with a naturally aspirated 6-pack and the second with a twin-scroll turbocharger (TSTC) mounted on the same engine.
Both models carry an electronically controlled all-wheel-drive (AWD) mechanism that BMW calls xDrive.
Model nomenclature becomes X3 xDrive28i (the non-turbo) and X3 xDrive35i (the turbo).
The all-aluminum in-line six-cylinder plant displaces 3.0 liters and has dual overhead cams (DOHC), direct injection (DI) technology and variable valve timing (VVT).
The naturally aspirated version produces 240 hp at 6600 rpm and 221 lb-ft of torque at 2750 rpm.
The turbocharged X3 bumps up to 300 hp at 5800 rpm with torque climbing to 300 lb-ft between 1300 and 5000 rpm.
Each engine links to an electronic automatic transmission with eight forward gears and Steptronic mode for manual shift control.
BMW's xDrive AWD mechanism distributes the engine's power to whichever axle, front or rear, attains the best traction bite. Transfer of torque occurs through a multi-disc clutch that's totally variable and virtually seamless.
It works with BMW's computerized four-wheel Dynamic Stability Control (DSC-X) mechanism and a traction control system (TCS-X) that can correct potentially dangerous car skid movements when wheels slip laterally or tires spin.
The xDrive mechanism normally channels 100 percent of the engine's muscle to the rear wheels, but slippage of a back wheel may prompt the smart system to redirect up to 40 percent of the torque to front wheels that still grip.
Off pavement, X3 adds another sophisticated device called Hill Descent Control (HDC) to keep all wheels firmly planted on a steep slope.
First-generation X3 models ran from 2004 to 2010, with the second-generation X3 -- completely redesigned with a slightly smaller package size yet more cabin room for riders and cargo -- rolling out of BMW's Spartanburg, S. C., assembly plant in 2011.
Generation 2.0 X3 issues for model-year 2012 show streamlined body styling, enhanced cabins filled with high-quality materials and high-tech electronic devices, revamped suspension designs with the option of a Dynamic Handling package installing adaptive suspension dampers and driver-choice driving modes, plus the two new powertrains.
Massive disc brakes mount at all posts and brakes tie through computer links to an anti-lock brake system (ABS) with electronic brake force distribution (EBD) and automatic brake drying (ABD), plus the TCS-X and DSC-X controls.
X3 xDrive28i rolls on 17-inch alloy wheels with 245/55R17 run-flat tires and stocks power controls for windows and door locks, 8-way power controls for front bucket seats, leatherette vinyl seat upholstery, a tilting-telescoping steering wheel wrapped in leather with tabs to control the audio, automatic climate system, cruise control, BMW's iDrive electronics interface, Bluetooth connectivity and a 12-speaker audio kit with AM/FM/CD/MP3/HDR/USB.
X3 xDrive35i scores 18-inch alloys capped by 245/50R18 run-flat tires and adds gear like adaptive xenon headlamps, real wood trim in the cabin and a panoramic sunroof.
Options are numerous, ranging from Nevada leather upholstery to heated front seats, folding rear seatbacks with 40/20/40 split, keyless entry device, power controls for the tailgate, rearview camera and Park Distance Control, dashboard navigation system, premium audio system and lots of packages -- Sport Activity, M Sport, Technology, Convenience, Premium, Cold Weather, Dynamic Handling.
BMW's compact-class wagons bring MSRP figures starting at $37,200 for X3 xDrive28i.