The Mercedes-Benz GLS 450 might combine a petrol engine with a big SUV, but it works rather well

For quite a few years, the very concept of a large Sports Utility Vehicle (SUV) with a petrol engine might have seemed like anathema, unless and until you bought the madcap variants like the AMGs and Ms of the world. Why would anyone buy a large SUV with a “normal” petrol engine? Okay so in these cases, normal engines usually mean three-litre V6 turbocharged engines, but you get the point. Then, of course, came that momentous Supreme Court ruling that in a single stroke wiped five years off the life of diesel-engined SUVs in the National Capital Region (NCR). While you can still fully depreciate a car in less than 10 years, it still hurts many owners to dispose of their big diesel SUVs after eight-nine years for a song. There are immaculately maintained 2010 and 2011 registered luxury diesel SUVs in the NCR that are available for next to nothing, if you check the online classifieds.

While we can, and should have a debate on whether diesel vehicles conforming to the BS6 emission regulations should be allowed the regular 15-year registration period, the ‘10-year rule’ has led to most manufacturers launching petrol-engined variants of all their SUVs and some manufacturers such as Maruti-Suzuki and Skoda-Volkswagen Group in India getting out of the diesel market altogether. However, the prevalence of petrol SUVs has puzzled some, after all, don’t petrol-engined SUVs return a far poorer fuel economy than a diesel-engined SUV?

Recently, I took the Mercedes-Benz GLS 450 out on a highway run to Jaipur and back. If the traffic on the highway is any indication, the economy is certainly back on track. Trucks still drive in the wrong lane and block the entire roads, being a trucker is a hard life, but for crying out loud, learn to drive properly folks and follow lane discipline. Driving on all but a few highways in India is a constant task of weaving through the traffic and while you are almost always in motion, you are constantly accelerating and braking. And with new cars coming with speed alarms, even at 80 kilometers per hour (less than the highway speed limit), which on most luxury cars sound over the music, you can’t even drive at the prescribed limit. I had a child in my car so I did not push the limit at all.

This car has a three-litre turbocharged inline-six motor with a battery that provides a power boost (Mercedes calls it EQ Boost) and start-stop help and makes the car a mild hybrid. Total power output is just over 360 horsepower and despite weighing over three tons with passengers and luggage and still gets a move on. But on the highway and a little bit of city driving the GLS450 returned a quite remarkable 9.5 kilometers per litre. Frankly, I do not feel that the diesel variant the GLS 400d would have done much better in the circumstances. And when you consider that the diesel and petrol variant cost the same ex-showroom, although on-road prices will be impacted by diesel vehicle taxation in some states like Delhi, the petrol variant makes a lot of sense particularly when you consider aspects like resale value.

As for driving the car, I have never been a huge fan of cars of the GLS’ size, but with button operated second and third-row recline, the GLS is easy to configure and can swallow a decent amount of luggage even with the third-row up and a positively massive amount of luggage when you have the third-row down. The SUV has a brilliant Burmeister sound system and on the front-row there are ‘Active Seat Kinetics’ which pulsate and believe me help a lot to mitigate fatigue, because a few hours on an Indian highway is like a full day of driving in Europe or the US.

While a GLS may be a bit big for me personally, the advent of lean-burning petrol engines in SUVs coupled with mild or strong hybrid systems will make a compelling case for them. And while it is too soon to declare the ‘Death of Diesel’, petrol-engined SUV’s are no longer fighting an uphill battle.