MOT cost .

Mercedes Benz

Gls

2,252 MOT tests analysed. sits above the UK fleet average — here's where Glss pass, fail, and end up on the retest sheet.

That's 12.8 points above the UK fleet average across our 1,988 tracked models — a confident result.

Pass

88.5%

Pass-after-fix

1.7%

Fail

9.2%

Avg miles

51,480

Pass + Pass-after-fix + Fail = 100%

The picture

Gls: a strong MOT record by UK norms

Across 2,252 MOT tests, the Gls returns 88.5% first-time pass — comfortably ahead of the UK fleet average. The single most-logged Major fail is tyre tread under the limit. A split CV-joint boot and windscreen damage round out the top three. Average tested mileage sits at 51,480, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.

Top ten reasons for rejection.

  1. 01

    Tyre tread depth not in accordance with the requirements

    91 occurrences · 4.0% of tests

  2. 02

    A transmission shaft constant velocity joint boot severely deteriorated

    88 occurrences · 3.9% of tests

  3. 03

    Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view

    66 occurrences · 2.9% of tests

  4. 04

    A tyre seriously damaged

    53 occurrences · 2.4% of tests

  5. 05

    A tyre cords visible or damaged

    39 occurrences · 1.7% of tests

  6. 06

    a brake lining or pad worn below 1.5mm

    23 occurrences · 1.0% of tests

  7. 07

    Brake lining or pad worn down to wear indicator

    16 occurrences · 0.7% of tests

  8. 08

    Number plate does not conform to the specified requirements

    15 occurrences · 0.7% of tests

  9. 09

    Wiper blade defective

    13 occurrences · 0.6% of tests

  10. 10

    A tyre seriously damaged

    12 occurrences · 0.5% of tests

Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.

Worst-case fix budget · top 2 failures

£120£190

If every one of this Gls's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →

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Tools that pre-empt a retest.

Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.

Buying or keeping a Gls?

Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.

If you own a Gls and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.