Mercedes-Benz GLS Review

Find out more about the Mercedes-Benz GLS in the latest Motors.co.uk Review

Out of 10
Average Price £65,548
Model Review

Mercedes launched the GL as a large luxury SUV in 2006, positioned above the ML (now called GLE), which rivalled the Audi Q7 that was launched the same year.

In 2012, the GL was facelifted and made even more luxurious and tech laden. The facelift even spawned a monstrous V8 powered GL 63 AMG model.

In late 2014, Mercedes announced it was changing the names of multiple models, one of these being the GL. The GL’s name was changed to the GLS at the very end of 2015, with deliveries for the lightly facelifted model beginning at the start of 2016.

Latest Model

Since the GLS debuted at the start of 2016, not a lot has changed. The GLS remains a luxury and imposing SUV that is exceptionally capable of ferrying seven people around in comfort.

For the 2017 model year, the front was slightly redesigned, while the rear received a redesigned bumper and full LED rear lights.


Value for money

The new GLS starts at £71,430, which doesn’t sound too expensive compared to a Range Rover, but next to the Audi Q7, which starts at £50,060, it does look very expensive. Although, the GLS is exceptionally well equipped. Standard equipment includes keyless-go, lane tracking technology, 21-inch alloy wheels, a panoramic electric sunroof and Active Park Assist. The standard interior equipment includes a memory seat package, front and rear heated seats and a Harman Kardon sound system.

Above the AMG Line is designo Line which starts at £80,425. Extra equipment includes an ‘Active Curve System’ which enhances ride comfort, a closing aid for the doors and boot. The interior gets the ‘designo’ interior package, with designo upholstery, climatised front seats, rear sun blinds and thermotronic climate control for third seat passengers too. Used GLs are quite good value, although expect to pay high running costs. Early GLs start at around £15,000 with reasonable mileages, although we recommend avoiding these early cars and going for the facelifted GL which came out in 2012. A 2013/4 GL350 CDI would make the best option, these can be had for around £37,000, which represents excellent value for money.


Looks and image

While there was quite a significant facelift in 2012 for the GL, the GLS really has not changed visually since then. It remains one of the biggest SUVs on sale and is exceptionally imposing. However, it really is not a great looking car. Its looks do not hide the fact of just how big the GLS really is. The interior is slightly better, although it is due a significant update to put it on par with the superb interiors which now feature in the E- and S-Class models.

It is crammed with the finest quality materials though – as you would expect on a car of this price. The GLS is definitely best suited to image conscious families, who need – or in most cases probably want – a large SUV.

Driving dynamics are not a strong point of the GLS. While the sheer pace of the GLS 63 AMG is seriously impressive, it is flawed as soon as you enter a corner. The top heavy stance of the GLS makes it a dynamic nightmare, where you can’t push it safely into corners, although in a way you probably wouldn’t want to.

On the plus side, the GLS has a very impressive ride, particularly on the motorway where it is best suited. The GLS even comes with air suspension as standard, which simply smothers out bumps in the roads. The only downside is that those large wheels can hamper ride comfort at lower speeds, although not significantly. It is definitely one of the most relaxing cars you can drive, particularly when paired with a new nine-speed gearbox.

Space and Practicality

As you would expect for its size, the GLS is one of the most spacious cars on the market, and the category which the GLS absolutely excels in. It is an enormous car, 110mm longer than a Range Rover, which means the cabin is huge. Even with all seven seats up, you still get 295-litres of boot space, and 680 litres with the third row of seats folded. However, leave just the two front seats in place and you have an enormous 2,300-litres of room, which is approaching van territory. The sheer size of the GLS does make parking it in tight car parks a bit of a nightmare, although parking sensors help you to manoeuvre it.

The GLS has never actually been tested by EuroNCAP, and therefore it doesn’t have a safety rating. However, the GLS does come with an array of safety equipment, that would probably grant it a five-star rating. It comes with lots of airbags, as well as lane departure warning and automatic braking systems, minimising your chance of getting in a crash in the first place.

Family appeal is where the GLS excels. The sheer size and space makes it one of the best SUVs for carrying people around. There is easily enough room for seven people to be carried in comfort, as well as room for luggage. While the GLS’ size may be intimidating for some people, it is absolutely ideal if you are in the market for a large, luxury family-friendly SUV.



Mercedes only actually offers two engines in the GLS, one petrol and one diesel, that couldn’t be more different if they tried. The diesel is a 3.0-litre V6 engine which comes as standard with 4 Matic – Mercedes’ four-wheel-drive system. It produces 255bhp, 620Nm of torque, and is coupled with a 9-speed automatic gearbox. At the other end of the spectrum is the fearsome 5.5-litre V8 petrol in the GLS 63 AMG. It produces a huge 577bhp and 760Nm of torque. This also comes with 4 Matic, but has a seven-speed AMG ‘speedshift’ gearbox instead.


Running Costs

If running costs are important, the best advice we could give is for you to stay clear from the GLS63. Fuel bills will be astronomical, as it produces a claimed 23mpg, and you will be extremely lucky to see 20mpg. It also produces a whopping 288g/km CO2. This means you will pay £2,000 in tax, as well as a £310 supplement because the GLS costs over £40,000. Even the diesel doesn’t fair that much better, as it only returns a claimed 37.2mpg, and produces 199/km of CO2 - meaning £1,200 for the first year in tax.

Insurance will be expensive too, both the petrol and diesel GLS are in the top insurance group of 50.

Things to look out for

There are not too many common problems which have been reported on the GL and GLS, although owners have questioned the interior quality and power steering which tends to leak. One thing we would strongly recommend, when buying a used GL or GLS, is that it has been well maintained. Unsurprisingly, on a car of this luxury and size, repairs and maintenance will be expensive, which you definitely need to bear in mind if you are purchasing a used vehicle.



At the top end of the luxury SUV market, there are not too many rivals. Land Rover is where most of the opposition lies as a range-topping Discovery, Range Rover Sport and the normal Range Rover could all be rivals to the GLS. Elsewhere, the Volvo XC90 and Audi Q7 are also rivals, albeit far cheaper ones. However, the size of the GLS almost puts in a class of its own.



Depreciation may be a bit of a concern on the GLS, particularly on the AMG model which will plummet in value. The GLS is predicted to retain just 40 per cent of its value after three years, far less than the Discovery which retains 60 per cent.

We would recommend buying an ex-demonstrator or nearly new GLS as it will have lost that significant amount of initial value which makes it the best option.

Which GLS to Pick

Trims Explained

Just two trim levels are available on the GLS350d diesel, AMG Line and designo Line. There is only one trim available on the GLS63 AMG.


AMG Line includes AMG bodystyling all round, 21-inch wheels, heated front and rear seats, as well as a Command Online system, that features an eight-inch touchscreen.

It starts at £71,430.


On the designo Line trim level, it has a designo Nappa leather interior, climatised front seats that have a massage function, as well as Thermotronic climate control, which even includes interior air filters.

Designo Line starts at £80,425.


The GLS 63 AMG features 21-inch bi-colour alloy wheels with red brake callipers and an AMG sports exhaust. The interior includes AMG branding, AMG sports seats and a performance steering wheel.

In Summary

  1. Only two engines available
  2. Expensive to buy and run
  3. Incredibly spacious interior
  4. Would make an excellent large family SUV
  5. Heavy depreciation
  6. Nearly-new car makes the best option
  7. Huge road presence
  8. Thirsty to run
  9. Be aware of high tax on both the petrol and diesel
  10. Extremely comfortable