Mercedes-Benz GLS review

The GLS is a very heavy car, tipping the scales at almost two and a half tonnes. But thanks to the huge torque generated by its 3.0-litre diesel engine, it builds speed in an effortless way.

True, there can be a small delay before its automatic gearbox responds when you ask for a sudden burst of acceleration. However, this is nowhere near as obvious as it is in some rivals – we’re looking at you Audi Q7 – and most of the time the GLS’s shifts are suitably smooth.

Engine refinement also impresses; it’s easy to forget you’ve got a diesel under the bonnet. And, while the car’s big tyres generate a bit of road noise, wind noise is very well controlled – especially when you consider the size of the hole that the GLS is punching through the air.

Instead, it’s the way the car rides and handles that disappoints. No matter which mode you put the air suspension in, the GLS tends to wobble about like a jelly on a spin dryer, which is bad news for any passengers prone to travel sickness.

What’s more, it doesn’t exactly glide over bumps and potholes. The BMW X7 is better at disguising its bulk in corners, too, combining superior body control with more precise steering.

Like most big SUVs, the GLS will be more frequently seen traversing shopping centre car parks than rocky rural landscapes, but it should be able to cope easily with deep snow and cambered icy surfaces, particularly if you specify the optional Off-Road package, which brings low-range gears and special off-road driving modes.