Pros: Relatively thrifty fuel economy; diesel technology bundled with the lowest price tag in the GL lineup; more torque than the $86,175 GL550 model.
Cons: Diesel requires pricey AdBlue additive refill approximately every 15,000 miles; acceleration can be ponderous for performance hungry drivers
Diesel powerplants are a tough sell for U.S. buyers. Our cultural attachment to the gasoline-powered engine and reluctance to pay the premium for relatively new clean diesel technology tend to lead us back to familiar ground. Fighting that trend is the the Mercedes-Benz GL350 BlueTec. At $62,445, it comes at a $1,000 discount compared to its V8-powered GL450 sibling and a whopping $23,730 less than the top-shelf gasoline-burning GL550 model.
The GL350 BlueTec also comes with a significantly skimpier standard equipment list compared with the high-end GL550, but it does offer greater torque that helps pull its weight around town and at lower speeds. Despite their German origins, all GL models are built at Mercedes-Benz's plant in Tuscaloosa, Alabama.
Comfort & Utility
The basic GL350 BlueTec has a comfortable and spacious, if somber, interior. Its lengthy options list outlines just how much room there is for its $62,445 starting price to grow. If the COMAND-based navigation system, power liftgate and rear-view camera sound appealing, you'll want to spring for the $4,280 Premium 1 package. The Premium 2 package adds keyless go and a Harman Kardon Logic7 surround sound system for $6,330. Real leather will run you $1,930, all of which helps boost the sticker price to well within reach of the top-tier, gasoline-powered GL550 model.
The GL350 BlueTec offers roomy accommodations with third-row seating that's actually livable for normal-size adults. Cargo capacity is 43.8 cubic inches with the third row folded flat and 83.3 cubic feet when all but the front seats are laid down.
The GL350 BlueTec comes with many of the same standard and optional tech-related features you'll find on comparable SUVs, so let's focus on the techy highlights of its unique powerplant instead.
Using the latest common-rail injection technology, this turbocharged and intercooled 3.0-liter V6 only produces 210 horsepower, but it also manages to churn an impressive 400 lb-ft of torque, more than the most powerful GL550 model. Using a maintenance-free particulate filter that removes the nasty black soot commonly associated with older diesel engines, the BlueTec also incorporates an AdBlue system that injects an aqueous carbamide solution into the exhaust to convert nitrogen oxides into harmless nitrogen and water. The upside? Cleaner emissions. The downside? A costly refill of the 8.5-gallon AdBlue tank every 15,000 or so miles. DIYers can perform the task themselves for about $50, but we're guessing most BlueTec buyers will opt for the easier dealer solution, which costs somewhere between $200 to $300 a pop. That certainly cuts into the cost benefits of driving a diesel.
Performance & Fuel Economy
The Mercedes-Benz GL350 BlueTec can't compete with its gasoline-powered competitors when it comes to acceleration: 60 mph arrives at a leisurely 9.4 seconds.
Fuel economy is rated at 17 mpg city and 21 mpg highway-respectable figures, considering this big SUV's 5,512 pound curb weight. Mercedes-Benz claims a highway cruising range in excess of 550 miles, thanks to the GL350 BlueTec's 26.4-gallon tank.
There is a reassuring array of standard safety features on the GL350 BlueTec, among them PreSafe, which positions the power seats and closes windows and sunroof to protect occupants from an impending collision. The GL350 includes active head restraints for the front passengers and nine airbags throughout the cabin. Optional features include Blind Spot Assist and bi-xenon headlamps with active curve illumination. Mbrace is available by subscription, providing emergency services when summoned.
Safety-conscious Mercedes-Benz buyers might want to consider waiting for the 2013 GL350 BlueTec, which will include more innovative features like Attention Assist, Collision Prevention Assist, Crosswind Stabilization, and the more advanced mbrace2 system.
Stately and imposing, the GL350 BlueTec may be inwardly difficult to discern from its gasoline-powered stablemates, but on the road it takes on a different persona. Initial acceleration feels strong thanks to the diesel powerplant's torquey disposition, and peak pulling power extends from 1,600 to 2,800 rpm, although it peters out at higher engine speeds. The GL350 performs adequately during casual around-town driving thanks to the flexibility offered by its seven-speed transmission, but more aggressive drivers will likely miss the broader power spread and more satisfying acceleration offered by the V8 gasoline engines.
Thanks to the standard Airmatic suspension, which automatically adjusts ride height, the GL350 glides along smoothly, producing better handling than you might expect for a vehicle of this size.
Other Cars to Consider
Audi Q7 TDI - Audi's Q7 TDI comes with a starting price ranging from $51,450 to $63,950. The clean diesel Q7's supercharged 3.00liter V6 is capable of 0-to-60-mph runs in an impressive 7.7 seconds and delivers 16 mpg city and 22 mpg. Smaller than the GL-Class, the Q7 offers less seating room for its third-row passengers.
BMW X5 xDrive35d -BMW's $56,700 X5 xDrive35d isn't quite a fair comparison since its smaller footprint and so-called seven-passenger seating layout features a third-row option that isn't really capaciousness enough for two fully grown adults. It's also sportier and nimbler than the Mercedes. More enticing for performance-minded drivers, this BMW boasts sharper handling and a 0-to-60 mph time of only 6.9 seconds.
Cadillac Escalade Hybrid - This nearly-$74,000 hybrid offers a flashier exterior and cushier interior than the GL350 BlueTec and best-in-class fuel economy numbers: 20 mpg city and 23 mpg highway. But this big Caddy's downsides include unrewarding handling characteristics and disconcerting brake feel.
The 2013 model is coming soon, with several of the best of Mercedes' safety features available on it.