Mercedes-Benz GLS common problems and MOT failures
What goes wrong on a used Mercedes-Benz GLS, year by year: known faults from UK buying guides, the parts flagged at MOT more than on other cars (from 8,022 MOTs done during 2023–2025), and what to check before you buy one.
Pick the year
Most years have their own guide. The year is when the car was first registered (it’s on the logbook, or check the reg below).
What usually goes wrong with a Mercedes-Benz GLS?
We haven’t found widely reported faults for the Mercedes-Benz GLS in the UK buying guides we use yet. That doesn’t mean it has none, so check the car carefully and look at the MOT weak spots below.
Common Mercedes-Benz GLS MOT failures to check
Parts flagged at MOT well above the usual rate for cars the same age, for each fuel on its own. From the DVSA’s results for every MOT done in Great Britain during 2023–2025.
Diesel
Drive shaft (CV) joints
up to 10× usualStands out on cars registered in 2017, 2018 and 2019.
Rough price £60–£350 our estimateAt the viewing: Drive slowly on full steering lock in both directions and listen for clicking. Look for split rubber boots behind the front wheels.
Mercedes-Benz GLS MOT pass rate by year
Of the years since 2005 with plenty of MOT tests, the 2016 Mercedes-Benz GLS did best (87% passed first time, 10 points above all 2016 cars) and the 2021 did worst (86%, 1 point below all 2021 cars). Older cars fail more, so compare each year with all cars registered the same year.
Questions to ask the seller before buying a Mercedes-Benz GLS
Ask before you travel to see it. A seller who knows the car will have answers, and receipts.
- Any recent work on the drive shaft (cv) joints? (Flagged at MOT 9.2× as often on the Mercedes-Benz GLS as on other cars the same age.)
- Can I see the service history and receipts for any big jobs?
Looking at a Mercedes-Benz GLS?
Check the actual car: its own MOT history, whether it already shows these weak spots and what to ask the seller. Free, no sign-up.
Where this comes from: MOT figures are the DVSA’s anonymised results for every MOT test done in Great Britain during 2023–2025, grouped by the year each car was first registered. How many are on the road is from the Department for Transport’s vehicle licensing statistics. Known faults are from UK buying guides, in our own words, with links. How we score