Used car guide · 2005–2023

Mercedes-Benz CLS common problems and MOT failures

What goes wrong on a used Mercedes-Benz CLS, year by year: known faults from UK buying guides, the parts flagged at MOT more than on other cars (from 70,714 MOTs done during 2023–2025), and what to check before you buy one.

70,714MOTs done in 2023–2025, all years of this model
25,067on the UK register
2005best year at its MOT

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).

2023202220212020201920182017201620152014201320122011201020092008200720062005

What usually goes wrong with a Mercedes-Benz CLS?

We haven’t found widely reported faults for the Mercedes-Benz CLS 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 CLS MOT failures to check

Parts flagged at MOT well above the usual rate for cars the same age, in more than one year. From the DVSA’s results for every MOT done in Great Britain during 2023–2025.

  • Wheel bearings

    up to 9× usual

    Stands out on cars registered in 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 and 2017.

    Rough price £120–£300 (one bearing) ClickMechanic

    At the viewing: Listen for a hum or growl that changes as you steer at speed.

  • Wheels

    up to 18× usual

    Stands out on cars registered in 2006, 2007, 2008, 2013, 2014, 2015, 2016, 2017, 2018, 2019 and 2020.

    Rough price £70–£150 our estimate

    At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.

  • Ball joint

    up to 10.2× usual

    Stands out on cars registered in 2005, 2006, 2007, 2008, 2009, 2010, 2018, 2019 and 2020.

    Rough price £60–£150 (one joint) ClickMechanic

    At the viewing: Listen for knocking over bumps and check the rubber boots behind the wheels aren't split.

  • Rigid brake pipes

    up to 6.6× usual

    Stands out on cars registered in 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 and 2014.

    Rough price £100–£400 our estimate

    At the viewing: Ask to see underneath, or check the MOT advisories: corroded brake or fuel pipes get worse every year and fail the MOT when they do.

  • Link ball joint covers

    up to 4.6× usual

    Stands out on cars registered in 2012, 2013, 2014, 2015 and 2016.

    Rough price £60–£150 (one joint) ClickMechanic

    At the viewing: Listen for knocking over bumps and check the rubber boots behind the wheels aren't split.

  • Steering rack inner joints

    up to 2.9× usual

    Stands out on cars registered in 2008, 2009 and 2010.

    Rough price £100–£450 our estimate

    At the viewing: On a straight road the steering wheel should sit straight. Listen for knocks when turning, and check the steering feels even.

Mercedes-Benz CLS MOT pass rate by year

Of the years since 2005 with plenty of MOT tests, the 2005 Mercedes-Benz CLS did best (71% passed first time, 14 points above all 2005 cars) and the 2020 did worst (79%, 8 points below all 2020 cars). Older cars fail more, so compare each year with all cars registered the same year.

YearPass first timeAll cars that yearMOT tests
202179%87% -8111 (small sample)
202079%87% -8854
201983%85% -23,235
201882%83% -12,898
201781%80% +14,487
201680%77% +36,312
201580%74% +68,678
201476%70% +65,369
201374%67% +79,199
201275%64% +113,346
201174%62% +123,529
201065%60% +53,206
200965%59% +63,285
200867%57% +104,060
200767%57% +105,119
200669%56% +134,213
200571%57% +142,813

Questions to ask the seller before buying a Mercedes-Benz CLS

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

  1. Any recent work on the wheel bearings? (Flagged at MOT 9× as often on the Mercedes-Benz CLS as on other cars the same age.)
  2. Any recent work on the wheels? (Flagged at MOT 18× as often on the Mercedes-Benz CLS as on other cars the same age.)
  3. Any recent work on the ball joint? (Flagged at MOT 10.2× as often on the Mercedes-Benz CLS as on other cars the same age.)
  4. Can I see the service history and receipts for any big jobs?

Looking at a Mercedes-Benz CLS?

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