Parkers overall rating: 4 out of 5 4.0

Miles per pound (mpp) Miles per pound (mpp)

Reliable fuel consumption data for comparison purposes is not available for this model.

Fuel economy

A more stringent standard for fuel economy (WLTP) was introduced from September 2017, and this model was not required to undergo that test. Its fuel economy measured under the previous test system was 36 - 36 mpg. However these figures are less likely to be achievable in real world driving and so should never be compared to another car's mpg which was measured under the newer, more realistic WLTP system.

As a large, heavy 4x4 powered by a 3.0-litre diesel engine, Mercedes-Benz GL-Class running costs aren’t going to be inexpensive.

That turbocharged V6 engine not only produces 254bhp, but it has to haul around almost 2.5 tonnes of bodywork, driving all four wheels through an automatic gearbox.

An average combined fuel consumption of 35.3mpg was produced in specific laboratory conditions – in the real world, 30mpg is a more realistic target with very gentle driving.

With CO2 emissions of 209g/km, the GL350 BlueTEC falls into expensive VED car tax band K, although it’s worth noting there are two bands even more costly than that.

Powered by a 3.0-litre V6 diesel engine, Mercedes-Benz GL-Class emissions are high compared to many other seven-seaters.

Subsequently, the GL350 BlueTEC is in band K for VED car tax.

No car is mechanically infallible but with the firm’s strong reputation for longevity we would expect Mercedes-Benz GL-Class reliability to be excellent.

The 3.0-litre diesel engine, seven-speed automatic transmission and four-wheel drive system are proven units, demonstrating the kind of robustness that provides long-term reliability both on- and off-road.

Its three-year warranty is in line with the class norms but the unlimited mileage aspect of it isn’t, suggesting Mercedes itself has faith in its mechanical strength. Maintaining a regular service history will also help overall reliability.

Build quality is a strong point although some of the materials feel a little more downmarket than you’d expect to find at this price point.

Ongoing running costs

Road tax (12 months) £330
See tax rates for all versions
Insurance group 49
How much is it to insure?