Performance by cohort

3 year bands · 139,037 tests

Pass rate climbs 5.6 points across the cohorts — newer Glc examples clear the test more reliably than the early cars.

Pre-2018 cohort 66,848

Pass

88.2%

Fail

9.8%

PRS

1.6%

Avg mileage at test

63,607 mi

2018–2020 cohort 65,478

Pass

90.4%

Fail

7.6%

PRS

1.7%

Avg mileage at test

44,386 mi

2021+ cohort 6,711

Pass

93.8%

Fail

4.6%

PRS

0.9%

Avg mileage at test

29,312 mi

Cohort = vehicle's first-registration year band. Same model, different generations of build.

Generations on file · 2

Mercedes Benz Glc · UK market

Photos: Wikimedia Commons · CC BY-SA / CC BY / public domain.

The picture

Mercedes Benz GLC: solid MOT record across 69,329 tests

The Mercedes Benz GLC is a diesel-powered car sold in the UK market across multiple generations, covering a broad date range in the test population.

MOT data from 69,329 tests puts this car on an 88.4% first-time pass rate, well above the UK fleet average. Average mileage at test is 45,435 miles. The most common fail item is worn suspension pin or bush, followed by cracked or discoloured windscreen.

For used buyers, the GLC's pass rate suggests it clears the MOT with fewer surprises than most — but the top failure items above are still worth a pre-purchase inspection, particularly on higher-mileage examples.

ABI Insurance Group

Group 32–44

A high-group car — insurance costs will be significantly above average. Lower groups cost less to insure; UK fleet average is around Group 22.

Source: ABI Group Rating Panel · administered by Thatcham Research · groups cover standard variants; performance trims may sit higher. Browse all insurance groups →

32–44

out of 50

Compare quotes →

Top ten reasons for rejection.

Filter failures:

Hide wear items to see the model's real defects.

01

A suspension pin, bush or joint excessively worn

2,885 occurrences · 2.1% of tests
02

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

2,532 occurrences · 1.8% of tests
03

Tyre tread depth not in accordance with the requirements

2,035 occurrences · 1.5% of tests
04

A tyre seriously damaged

1,652 occurrences · 1.2% of tests
05

A tyre cords visible or damaged

1,168 occurrences · 0.8% of tests
06

Wiper blade defective

900 occurrences · 0.6% of tests
07

a brake lining or pad worn below 1.5mm

820 occurrences · 0.6% of tests
08

Engine MIL illuminated indicating a malfunction

591 occurrences · 0.4% of tests
09

A transmission shaft constant velocity joint boot missing or no longer prevents the ingress of dirt etc

573 occurrences · 0.4% of tests
10

A spring or spring component fractured or seriously weakened

528 occurrences · 0.4% 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 3 failures

£200–£430

If every one of this Glc'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 →

Try the calculator

Build your own retest budget.

Year-band analysis

Best year to buy. Worst to avoid.

First-time MOT pass rate split by registration band. A 5.6-point gap between bands means the year you buy Mercedes Benz Glc has a real effect on what turns up at the garage.

Best band to buy

93.8%

2021+ registration

the 2021-on band climbs to 93.8% — a 5.6-point improvement. Tests in this band average 29,312 miles — roughly 34K miles fewer on the clock than the older band. Failures here are mostly wear items: damaged but not adversely affecting driver's view, has a cut in excess of the… — the structural issues that drag down older examples don't appear in the top-10 for this band. Post-2020 examples are early in their MOT life and generally show the cleanest records.

Band to be cautious about

88.2%

Pre-2018 registration

On the older band (pre-2018), the data shows a 88.2% pass rate against a fleet average of 93.8% on the newer band. The main culprits logged at test: ball joint excessively worn, damaged but not adversely affecting driver's view, and tread depth below requirements of 1.6mm. Average mileage on test for this band is 63,607 miles — high-mileage wear items are a recurring theme.

Best band to buy: 2021+ (93.8% first-time pass). Worst band to avoid: pre-2018 (88.2% pass). That's a 5.6-point spread across 66,848 older tests and 6,711 newer ones — year of build makes a material difference on this model.

Year-spread leaderboard →

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.

Item 01 · Amazon UK

Digital tyre-tread depth gauge

Five quid for a gauge beats £150 for a retest. UK MOT minimum is 1.6mm — most testers fail anything below 2mm to be safe.

Search Amazon UK

My Motor World · affiliate

Parts & supplies for this fix

Affiliate links — small commission, no extra cost to you.

Denso

Denso W14E Spark Plug (Single)

£1.09

View at My Motor World →

Denso

Denso W16EX-U Spark Plug (Single)

£1.09

View at My Motor World →

Denso

Denso W16FSR Spark Plug (Single)

£1.09

View at My Motor World →

Denso

Denso W9LM-US Spark Plug (Single)

£1.09

View at My Motor World →

Click Mechanic · affiliate

Book a mobile mechanic

Affiliate links — small commission, no extra cost to you.

Mobile mechanic · UK-wide

Book a mechanic at your door.

Fixed-price quotes upfront. No garage needed. Click Mechanic sends a vetted local mechanic to you — home, work, or roadside.

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Recall history

67 UK recalls on record.

The Glc has 67 official UK vehicle recalls covering defect details, remedies, and affected build dates.

See all recalls

Buying or keeping a Glc?

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 Glc 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.