Bounding through the western Colorado countryside on an early spring day, the only snow in sight capping the tops of local mountains, it almost felt like cheating to be luxuriating behind the wheel of the all-too-capable, overachieving 2017 Mercedes-Benz GLS-Class. You will come to know the GLS as the successor to the GL sport-utility vehicle, a popular and well-rounded fixture of wealthy suburbs and determined Brooklyn parkers. FOLLOW DAILY NEWS AUTOS ON FACEBOOK. Haven鈥檛 we seen you before? If you think the new 2017 GLS-Class looks an awful lot like the GL, you鈥檙e not wrong. An evolution of the GL鈥檚 proven design of the GL, and depending on who you ask at Mercedes-Benz, the GLS has turned either more aggressive, thanks to added bluntness in the nose, or softer and more feminine. Save for a revised grille and new, oversized taillights, I see the same shape as the GL. Finding the sweet spot in a lineup as wide-ranging as GLS鈥?is tricky.

New nomenclature differentiates the diesel-powered model (GLS350d) from the gas-powered V6 and V8 models (GLS450 and GLS550, respectively), and the one tuned by Mercedes-AMG (GLS63). Now that model namesno longer haveanything to do with engine size or output, it can be difficult to discern which one makes the most sense. Mercedes-Benz expects the GLS450to find favor with a majority of buyers, who will no doubt enjoy its3.0-liter, 362-horsepower,twin-turbocharged V6. The GLS550 soldiers on with a 4.7-liter, 449-hp twin-turbocharged V8, while the bonkers GLS63 retains its hand-built 5.5-liter, 577-hp twin-turbocharged V8. Expected to return as the entry-level engine is a 3.0-liter, 255-hp turbodiesel that boasts enough torque (457 lb.-ft.) to tow 7,500 pounds. Undoubtedly, mypreferenceisthe GLS63, but the GLS350d and GLS450 have more than enough power to satisfy daily driving requirements.Notably, a9-speed automatic is now standard in the GLS350d, GLS450, and GLS550, while the GLS63 retains the outgoing 7-speed automatic. Interestingly, Mercedes-Benz is remarkably conservative with GLS body styles and powertrain options.

Unlike the M-Class-turned-GLE, which added a plug-in hybrid to itslineup in addition to a four-door 鈥渃oupe鈥?modeled after the BMW X6, neither enhancement is on the table for the GLS. A ultra-luxurious Mercedes-Maybach edition of the GLS is reportedly in the works, although no one from Mercedes-Benz has confirmed it yet. By adding an 鈥淪鈥?to the GL name, Mercedes-Benz hopes to associate the GLS as a complement to theflagshipS-Class sedan, an attempt to reposition the SUV using the same method that turned the M-Class into GLE. In so doing, however, Mercedes-Benz finds itself the victim of its own success. Plainly put,the GLS is little more than a refresh of the 2016 GL, and therefore falls significantly short of the pedigree established by the S-Class. For a fine example of harmonious interplay between an SUV and its sedan and coupe counterparts, see the recently launched GLC-Class SUV, which quite literally elevates everything that we love about the C-Class. The most telling sign that the GLS is merely an upgrade from the GL, rather thanan overhaul, is that the interior remains virtually the same, both in terms of its quality and itsfeature content.

The most significant changes includethe additionof Mercedes-Benz鈥檚 latest infotainment system and a new three-spoke steering wheel. That hardly represents a full-on adoption of the incredible levels of style, luxury, and technology that differentiate the S-Class from its competition. Or the incredible digital instrumentation? If Audi canturn the Q7into a powerhouse of technology, we believe that Mercedes-Benz could have done the same. Despite what we perceive to be shortcomings within the interior, the GLS remains a refined, capable companion on a road trip of any duration. Regardless of which engine you choose, the GLS feels powerful at any speed, with plenty more on reserve. Fuel economy isn鈥檛 amazing for the segment, butthe V6-powered GLS450 returns a respectable 19 mpg in combined driving. It鈥檚 incredibly easy to put away miles when you鈥檙e behind the wheel of a GLS, as Ilearned while driving across vast stretches ofColorado and Utah. Steering feel is light but accurate, without too much artificialitydialed in.