Mercedes Benz Glc (2018)

19,930 real MOT outcomes analysed • 90.7% first-time pass rate

2018 Mercedes Benz Glc

CarHunch analysed 19,930 real MOT records for the 2018 Mercedes Benz Glc. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

The 2018 Mercedes-Benz GLC is genuinely reliable, with a 90.6% first-time pass rate that beats the UK average by over 10 percentage points. However, 18.5% of these cars have recorded a dangerous defect at some point, which is worth factoring into your inspection—petrol versions hold a slight edge over diesel at 92.0% versus 90.2% pass rates.

These GLCs average just 42,000 miles at test, suggesting well-maintained examples in the used market, though each vehicle typically racks up 0.6 failures and 4.3 advisories per MOT, pointing to wear on suspension and trim items rather than fundamental mechanical problems. Before buying, ask the seller for the full MOT history and have a pre-purchase inspection focus on the suspension and any previous dangerous defect recordings.

Average reliability 10.7% above UK average
90.7%
pass MOT first time
UK average: ~80%
42,091
typical mileage
32,793–53,125 middle half
18.5%
ever had a dangerous defect
recorded at any MOT
0.6
avg MOT failures per car
over 5.5 tests on record

Petrol vs Diesel

Pass rate difference of 1.8 percentage points — worth knowing if you're choosing between the two.

92%
Petrol
4,830 vehicles
90.2%
Diesel
15,100 vehicles

What to check before buying a 2018 Mercedes Benz Glc

Practical pre-purchase checks for this age and model.

  • 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
  • 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
  • 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
  • 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.

Before you buy a Mercedes Benz Glc

MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.

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Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Diesel (76%) 15,100 90.2% 0.64
Petrol (24%) 4,830 92% 0.5

Mileage Distribution

Most 2018 Mercedes Benz Glc vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.

32,793
low mileage
42,091
typical
53,125
high mileage

Half of all 2018 Mercedes Benz Glc vehicles fall between 32,793 and 53,125 miles.

2018 Mercedes Benz Glc — Still on the Road

Strong survival — 18,050 vehicles still getting MOTs in 2025, 94% of the peak.

19,142 18,050 2021 2025

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2021–2025.

MOT History Averages

5.5
Avg MOT tests per vehicle
0.6
Avg failures per vehicle
4.3
Avg advisories per vehicle

Most Common MOT Issues — 2018 Mercedes Benz Glc

Based on actual MOT test records for this model. Percentage shows how often each item appears across all vehicles in this cohort.

  • 33.8%
    Nearside Front Tyre worn close to legal limit/worn on edge
  • 30%
    Offside Front Tyre worn close to legal limit/worn on edge
  • 25.1%
    Nearside Rear Tyre worn close to legal limit/worn on edge
  • 24.5%
    Offside Rear Tyre worn close to legal limit/worn on edge
  • 21.5%
    Front Brake pad(s) wearing thin
  • 13.3%
    Nearside Rear Child Seat fitted not allowing full inspection of adult belt ()
  • 12.5%
    Rear Brake pad(s) wearing thin
  • 9.5%
    Offside Rear Tyre slightly damaged/cracking or perishing

Data covers a 3-year window centred on 2018. Counts include advisories and failures.

Found a specific Mercedes Benz Glc?

Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.

UK

Other model years — Mercedes Benz Glc:

2015 2016 2017 2019 2020 2021 2022