CALISTOGA, CA – The third new Mercedes-Benz utility vehicle in 18 months will reach dealer showrooms this spring, Ron Mueller, SUV product manager, says.

The GL “is targeted at traditional late-forming affluent families who can’t fit in smaller Mercedes SUVs,” he says.

Mercedes’ largest utility vehicle to date, although referred to by the auto maker as an SUV, actually is a unibody cross/utility vehicle, as are its linemates in Alabama. It will compete with the Cadillac Escalade, Lincoln Navigator and Infiniti QX56. (See related story: Zetsche Introduces Fullsize CUV, Stresses U.S. Diesels)

GL450 is Mercedes’ largest utility vehicle.

The GL is being assembled at Mercedes’ Vance, AL, plant. It does not replace the G-Class SUV that has been on sale for more than a quarter-century and will continue to be offered.

The GL is built on one of the plant’s two lines along with the M-Class SUV. A second line builds the R-Class CUV and M-Class.(See related story: Mercedes Moves E-Class Production But Steyr Retains G-Class)

Unlike the G-Class, which has a separate ladder frame and body, the GL is built on a unibody platform. High stress points between the suspension and body are highly reinforced to absorb high-load forces generated in off-road driving.

Mercedes says 54% of the body panels are made of lightweight, high-strength steel that helps hold overall weight to 5,300 lbs. (2,404 kg).

Mueller claims this is 300-600 lbs. (136-272 kg) less than competitive-sized utility vehicles. He also says the unibody construction provides more interior space.

The new CUV has standard third-row seating and accommodates seven occupants. Each seat has a reading light and cupholder.

Mueller says the third row is roomy, which along with a fixed skylight, eliminates the claustrophobia back-row passengers sometimes experience. An optional sunroof is offered.

Rear power-folding seats are standard and go from upright to flat in 4.9 seconds, Mueller claims. Overall cargo space exceeds 83 cu.-ft. (2.4 cu.-m) with the second and third rows folded flat.

With a 121-in. (308-cm) wheelbase and an overall length of 200 ins. (508 cm), the GL has a look that is sleeker than most fullsize utility vehicles.

It also is 75.6 ins. (192 cm) wide and 72.4 ins. (184 cm) tall, giving the vehicle a muscular look from the front and rear. Aerodynamics are enhanced by a respectable 0.37 coefficient of drag.

An all-new 4.6L V-8 engine powers the GL. It generates 335 hp and 339 lb.-ft. (406 Nm) of torque. The vehicle also comes with a 7-speed automatic transmission and 4MATIC fulltime 4-wheel drive.

The 4WD independent suspension has height-adjustable Airmatic springs with adaptive damping.

The automatic can skip up to three gear ratios when downshifting, if needed. It also has a lockup clutch that engages in all gears. During a test drive at a press introduction on the Napa Valley roads here, the transmission shifted imperceptibly, downshifting on hills smoothly.

A small stalk on the instrument panel controls the transmission. Soft touches shift the gears electronically. Drivers can control shifting manually, but a computerized controller prevents downshifts that would cause the engine to over rev.

The GL has a full complement of safety features to better protect occupants and pedestrians that includes eight airbags. The 2-stage front airbags have variable inflation rates controlled by the severity of an impact.

There also are front and mid-row side airbags and two full-length curtain airbags to prevent head injuries in side crashes.

Mueller says Mercedes plans to introduce a 3.2L diesel in the GL next year. However, it will be available only in 45 states. The 3.0L diesel, which is the same CDI found in the E-Class, generates 221 hp and a hefty 376 lb.-ft. (510 Nm) of torque.

A rear camera that gives drivers a view of the area behind the GL when in reverse will be available later this year.

Also available later in the year is an off-road package that will include a 2-speed transfer case with electronically controlled multi-disc locks on the center and rear differentials.

A rotary switch on the center console will allow manual engagement, or an automatic mode can be selected that locks the center differential whenever it detects wheel slippage.

Mueller forecasts only 2% of GL buyers will opt for the off-road package.

He says the GL will compete in a luxury segment that totals about 670,000 units, as Mercedes defines it. He predicts 50%-60% of GL sales will be incremental to Mercedes. That is a bit under the R-Class, whose conquest sales are about 75%.

The average transaction price of the GL likely will be in the low $60,000s, Mueller says. The starting price has yet to be announced, but he expects it to be in the high $50,000s.

Mueller declines to forecast GL sales for this year but says Mercedes’ overall utility-vehicle sales will account for one-third of its sales this year.

The Vance plant is operating two shifts at present, with output well below the 160,000-unit capacity. This would enable Mercedes to produce more GL units should market demand increase.

Unlike the M-Class, with about 60% of its sales as exports to 135 countries, Mueller expects 75% of GL volume to be sold in the U.S. Mercedes will offer right-hand-drive models to meet market requirements.