Mercedes-Benz is getting the all-new GLB ready for prime time by throwing it into the kind of cold most drivers only read about. Engineers at the Mercedes Technology Center in Sindelfingen are using climatic wind tunnels to simulate everything from a bluebird powder day to a whiteout with sideways snow. The payoff is a compact SUV that feels welcoming even when the thermometer sinks, with a first look inside revealing room for up to seven and an optional MBUX Superscreen that stretches across the dash. The world premiere lands on December 8, 2025.
Cold-weather tuning is serious business here. The GLB is being punished at temperatures as low as minus 40 degrees Fahrenheit, with snow cannons changing flake type and density while a high-powered fan whips up blizzard conditions that hit the car at up to 124 mph. Beneath the car, a rolling road powers four individual rollers, so 4MATIC models can be tested exactly as they would behave on a real street. The hardware is stout, with test rigs rated to a total of 1,046 hp and capable of simulating speeds up to 165 mph. Engineers sit in a nearby control room dialing in temperature, humidity, and wind speed, then watch the storm unfold through insulated windows.
Heat is part of the story too. In a separate chamber, the GLB faces up to 140 degrees Fahrenheit while 32 solar lamps deliver sunlight that mimics the real thing. There is even a Hot Road that warms the rolling surface between 122 and 158 degrees Fahrenheit to replicate blistering pavement. That combination lets Mercedes chase gremlins in both extremes and repeat tests with scientific precision.
The numbers from winter testing are encouraging. At an outside temperature of 5 degrees Fahrenheit, the GLB clears an icy windshield for safe driving in about 15 minutes using only the defrost setting, no driver intervention needed. Engineers also evaluate how swirling snow might choke air inlets, a real risk when following big rigs, and validate wiper performance so the system does not blink when heavy, wet flakes start to fall.
Comfort is the other headline. In 19-degree Fahrenheit ambient conditions, the new GLB warms its cabin roughly twice as quickly as its predecessor while using about half the energy, an efficiency gain that also helps preserve electric range. Heat arrives where you feel it first, with a strategy that prioritizes hands and upper body the moment you get in, even if you did not precondition.
A big reason is the multi-source heat pump adapted from the VISION EQXX program. It can harvest waste heat from the electric drive unit, the battery, and the surrounding air at the same time. Using this free energy, it achieves the output of a typical auxiliary heater while drawing roughly one third of the electrical power, which is a smart way to keep everyone toasty without denting range.
Inside, the design moves in a cleaner, more technical direction. The optional MBUX Superscreen appears to float across the full width of the dashboard, bracketed by circular climate vents that look like polished hardware. Door panels get a concave main surface with a large floating center section and a classic tubular pull handle that feels purposeful. The center console flows under the Superscreen and features a three-dimensional trim panel with integrated cupholders and a smartphone tray, and available wireless charging hides in plain sight.
Driver touchpoints have been rethought with an emphasis on intuitive control. Mercedes brought back a rocker switch for cruise control and the Digital Extra version of Distance Assist DISTRONIC based on customer feedback, and a roller switch now handles volume, a nice tactile win in a screen heavy world.
Space and flexibility improve as well. Five seats are standard and seven are available. Headroom grows for both the first and second rows, helped by the SUV roofline and a standard panoramic roof. Second row comfort takes a step forward with more legroom and longer thigh support, while an optional sliding bench lets you fine tune recline and fore aft position, and comes standard when you choose the third row. Access to that third row is easier thanks to a wider Easy Entry adjustment range, and when you need cargo space the seats drop into the load floor.
About that roof. The large panoramic setup uses laminated safety glass with an infrared reflective layer and a LowE coating on the inside surface. The tech helps keep heat out in summer and keep warmth in during winter. The infrared film is just 200 nanometers thick, a tiny fraction of a human hair, yet it makes a real difference in cabin comfort. If you want something a little theatrical, you can option switchable glass that flips between transparent and an opal translucent setting in 10 to 20 milliseconds, and pair it with ambient lighting that paints a starry sky across the panel.
The digital experience gets a full rethink with MB.OS, which turns the GLB into a rolling smart device. The fourth generation MBUX introduces a refined Zero Layer interface, new welcome animations, an MBUX Virtual Assistant with selectable avatars, and a wider app ecosystem. Navigation leans on Google Maps and adds powerful Surround Navigation for richer guidance. Under the skin, the GLB packs a water cooled high performance computer with headroom for future functions, supported by 10 cameras, five radar units, and a dozen ultrasonic sensors. Over the air updates and a standard suite of driver assistance features, including Distance Assist DISTRONIC, aim to keep the SUV feeling current long after it leaves the showroom.
From the way it shrugs off snow to the way it greets you with warmth, the all-new GLB is shaping up to be a winter friendly family hauler with a tech forward cabin and a smarter energy play. With the debut set for December 8, 2025, we will not have to wait long to see the full picture.
Lloyd Tobias is a seasoned automotive journalist and passionate enthusiast with over 15 years of experience immersed in the world of cars. Whether it’s exploring the latest advancements in automotive technology or keeping a close pulse on breaking industry news, Lloyd brings a sharp perspective and a deep appreciation for all things automotive. His writing blends technical insight with real-world enthusiasm, making his contributions both informative and engaging for readers who share his love for the drive. When he’s not behind the keyboard or under the hood, Lloyd enjoys test driving the newest models and staying ahead of the curve in an ever-evolving automotive landscape.
