In-depth reviews

Mercedes GLS review - MPG, CO2 and running costs

The GLS is a big, heavy car; even with a capable diesel engine it will cost a pretty penny at the pumps

Overall Auto Express Rating

4.0 out of 5

MPG, CO2 and Running Costs Rating

3.0 out of 5

Price
£108,200 to £181,850
Find your Mercedes GLS
Offers from our trusted partners on this car and its predecessors...
Or are you looking to sell your car?
Advertisement

There’s only so much a combustion engine – no matter how efficient – can do to offset the need to haul around a 2.5-tonne SUV. So while the 3.0-litre V6 diesel is a capable unit, at best it achieves 30.7mpg in official WLTP tests. Spend time driving in town and that number is likely to drop quite significantly. Despite the relative thirst, an enormous 90-litre fuel tank means that, should you match the official economy figures, the GLS will cover about 600 miles on a tank.

The Mercedes-AMG GLS 63, trading economy for extra performance, is only able to achieve a maximum 22.1mpg.

Prices for the diesel-powered GLS start from just over £75,000 and climb to around £92,000 before options. You'll need deeper pockets in order to be able to climb into one of the AMG versions, with the top-of-the-range GLS 63 Night Edition Executive version priced at an eye-watering £128,285.

Insurance groups

With such a hefty price tag, insurance costs aren’t likely to be cheap. Groupings for the GLE head right to the top of the 50 classifications available, so a big budget will be needed beyond the initial purchase price.

Depreciation

Depending on the trim level, the GLS is predicted to hold between 43 and 49% of its value over three years and 36,000 miles. That’s some way behind the BMW X7, which retains up to 56% over the same period.

Which Is Best

Cheapest

  • Name
    GLS 400d 4Matic AMG Line Premium 5dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £76,775

Most Economical

  • Name
    GLS 400d 4Matic AMG Line Prem + Exec 5dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £93,275

Fastest

  • Name
    Maybach GLS 600 4Matic 5dr 9G-Tronic
  • Gearbox type
    Semi-auto
  • Price
    £167,540

Most Popular

‘Forget leasing a car, a cut-price van should be your next everyday vehicle’
Opinion - Fiat Scudo
Opinion

‘Forget leasing a car, a cut-price van should be your next everyday vehicle’

With some huge savings to be had, Mike Rutherford thinks a van could be the perfect vehicle
3 Dec 2023
Deal of the Day: Spacious Skoda Superb is a peerless estate for £223 a month
Skoda Superb Estate - front tracking
News

Deal of the Day: Spacious Skoda Superb is a peerless estate for £223 a month

The Superb is one of our favourite estates and our Deal of the Day for Monday 4 December
4 Dec 2023
New Renault 5: price, specs, launch and on sale dates
Renault 5 EV concept at 2022 Goodwood Festival of Speed
News

New Renault 5: price, specs, launch and on sale dates

Renault’s reborn Renault 5 will start from €25,000 in Europe, suggesting a circa-£30k price in the UK. It's due on sale in the summer of 2024. Here's …
1 Dec 2023