The old adage, “if it ain’t broke, don’t fix it,” comes to mind when the topic of the iconic Mercedes-Benz G-Class comes up. The luxury off-roader enters a new generation for 2019, or perhaps the better descriptor is refined, as amid the upgrades inside and out the SUV retains a similar boxy, utilitarian appearance first introduced nearly 40 years ago that the vehicle has become known for.

On the outside, let’s start with the things that haven’t changed. The distinctive black pull-out door handles, parallel to the matching horizontal bump strip running along the entire side of the body, remain, as do the exposed door hinges and raised hood. The same goes for the spare wheel mounted to the swing-open rear tailgate and the flanking rectangular turn signal lamps, all designed to match the G-Class’ chiselled, angular character lines.

The subtle aesthetic modifications follow Mercedes-Benz’s Sensual Purity design philosophy, which is guided by the principle of enhancement while staying true to the subject’s original spirit. For example, the headlamps now sport efficient LED technology and house signature circular daytime running lights. Also, although not immediately noticeable, the entire vehicle is sized up gaining 53 millimetres in length and 121 millimetres in width. In the process, gaps between panels have been reduced and the wheel arches and bumpers smoothed over so as to look like part of the bodywork rather than tacked-on afterthoughts.

Almost everyone knows how opulent the German automaker’s interiors are, and the G-Class is no different seamlessly combining the ruggedness of the exterior with high class cabin comfort. A neat thing they’ve done is taken certain outer elements, such as the aforementioned headlamps and indicators, and replicated the shape in the air vents and stereo speakers, respectively. Carryovers from the last generation include the grab handle above the glove box and the three chrome differential switches on the center stack.

Again blending the contemporary and classic, the completely redesigned instrument panel has a retro feel but features the same virtual dials as the current E-Class and S-Class sedans. The style and colour of the electronic display, as well as information shown, can be modified by selecting a different visual mode such as “Sport,” and “Progressive.” To manipulate onboard settings and the infotainment system, users have the choice of inputting commands via a haptic-feedback-enabled central touchpad controller or voice.

Thanks to the larger footprint of the new G-Class, all passengers enjoy extra space. Legroom in the front grows by 38 millimeters in the front and 150 millimetres in the rear. The ergonomic seats are heated, and the driver receives a memory function that is handy for multiple operator households. Customers can bump up to the Active Multicontour Seat Package to add massage, cooling and fast-heat functionality.

Time to talk performance. Although for the purposes of this review I mainly conducted testing in the city and on highways, both on and off-road capability is more impressive than before. To accomplish the task, engineers have used a new mix of ultra-high-strength and lightweight steels and aluminum materials in constructing the frame, shell and accessories, resulting in an increase of torsional rigidity of 55 per cent.

Speaking of suspension, the system was designed in partnership with Mercedes-AMG. The independent layout boasting a double-wishbone front axle balances drivability between tarmac and less solid surfaces, and affords greater ground clearance if the route does turn off-road. Need to cross a body of water? No problem — the G-Class can ford water and mud at depths of 70 centimetres rather than the previous 60.

Last but not least, the powertrain. Under the hood of the G550 lies a 4.0-litre V8 engine, producing 422 horsepower and 450 lb-ft of torque for the G 550, mated to a 9G-TRONIC nine-speed automatic transmission. Fuel economy is not something to brag about, the big SUV averaging around 20.0 L/100 km in mostly city conditions. Those sitting behind the wheel have five different DYNAMIC SELECT settings to choose from (Comfort, Sport, Eco, Individual) that alters the driving feel, modifying engine, gearbox, suspension, steering and even computer assistance behaviour. A special G-Mode is reserved for when one of the differential locks or low range gear is activated, fine-tuning the above attributes to make travelling over rough terrain easier.