Premium mid-size SUV dominating the UK executive market
The GLC replaced the GLK in 2015 and quickly became Mercedes' best-selling SUV in the UK. First-generation models (2015-2022) now start from around £18,000-£25,000 for well-specced examples. It competes directly with the BMW X3 and Audi Q5. Diesel models make the most financial sense for UK buyers, with lower road tax on pre-April 2017 cars and significantly better fuel economy than petrol equivalents.
We track 5 known issues across the Mercedes-Benz GLC range, with 1 classified as significant. Knowing which variants and configurations to approach with caution can save you from expensive surprises after purchase.
Found a Mercedes-Benz GLC? Enter the reg to see which of our 5 known issues apply to that exact car, plus full MOT history and mileage checks.
X253.1 (2015–2019) — Petrol options included the 2.0 Turbo Petrol, 3.0 V6 Petrol, with 2.1 CDI Diesel, 3.0 V6 Diesel on the diesel side. We track 5 known issues on this generation, with 1 classified as significant. The most significant concern is Transmission flexible coupling deterioration (£800–£1,500 to address).
X253.2 (2019–2024) — Petrol options included the 2.0 Turbo Petrol, 3.0 V6 Petrol, 4.0 V8 AMG, with 2.0 Diesel on the diesel side. We track 5 known issues on this generation, with 1 classified as significant. The most significant concern is Transmission flexible coupling deterioration (£800–£1,500 to address).
The flexible coupling in the transmission driveline connects the transmission output to the propshaft on 4WD variants. This rubber-bonded component isolates vibration but deteriorates faster than expected on GLC models. MOT data shows this model fails at up to 1088.6 times the fleet average for this specific defect, primarily affecting V6 petrol variants. The coupling becomes excessively cracked or separated, causing vibration, noise, and eventual complete failure that leaves the car immobile.
Complete coupling failure results in loss of drive to the front or rear axle depending on configuration, leaving the vehicle unable to move under power. Replacement requires transmission removal in most cases. Vibration from a deteriorating coupling can damage other driveline components if left unrepaired.
Listen for clunking or vibration from underneath when pulling away or changing direction. Check for play in the driveshafts by rocking the car in gear with the handbrake on. Worn CV boots are a telltale sign — look for grease splatter around the inner wheel arch.
Multiple suspension components including control arm bushes, anti-roll bar links, and ball joints show accelerated wear on GLC models.
Worn suspension components reduce handling precision, increase stopping distances, and cause premature tyre wear. Multiple components typically require replacement together, increasing repair costs. The vehicle remains safe to drive but handling degrades progressively.
Listen for knocking, clunking or rattling over bumps during the test drive. Inspect the underside for corroded or cracked suspension components. Check the MOT history for suspension-related advisories, which often predict future failures.
GLC models show unusually high brake pad wear rates, particularly on 2.0 petrol variants where MOT failures occur at 41.2 times the fleet average for worn brake pads. The combination of relatively heavy weight, aggressive brake pad compounds, and regenerative braking system integration on some variants causes faster than normal consumption. Front pads typically require replacement every 20,000-30,000 miles in normal use.
Worn brake pads reduce braking efficiency and can score the brake discs if allowed to wear completely, significantly increasing repair costs. The brake wear sensors provide advance warning before safety is compromised. Replacement is routine maintenance but occurs more frequently than on comparable models.
Check brake disc condition for lipping or scoring. Test braking at moderate speed for pulling to one side or vibration through the steering wheel. Review MOT advisories for brake-related items.
Diesel GLC models show significantly higher rates of engine management light (MIL) activation, with 2.1-litre diesel variants failing MOT tests at The trend is worsening. Common triggers include EGR valve faults, DPF regeneration issues, and NOx sensor failures related to emissions control systems. Many activations are temporary and related to driving patterns rather than permanent faults.
An illuminated engine management light causes immediate MOT failure regardless of actual vehicle safety. Many causes are relatively minor such as faulty sensors or incomplete DPF regeneration cycles. However, some indicate more serious emissions system faults requiring specialist diagnosis and potentially expensive repairs.
Check all electrical functions systematically: windows, mirrors, lights, infotainment, heated seats, air conditioning. Look for any warning lights on the dashboard. A diagnostic scan before purchase can reveal stored fault codes.
The panoramic sunroof fitted to most GLC models develops mechanical failures preventing proper opening or closing. NHTSA data shows multiple complaints about sunroofs refusing to close, creating weather ingress risks. The motor mechanism, guide rails, or control module can fail, and the complex sliding panel design is vulnerable to debris contamination and seal deterioration that affects operation.
A stuck-open sunroof creates serious weather protection and security issues. Repair typically requires replacement of the entire mechanism including motor, rails, and control electronics. Water ingress from faulty sunroofs can damage interior electronics and create expensive secondary faults.
Check panel gaps are even and consistent all the way around the car. Look for signs of repainting — overspray on rubber seals, mismatched paint texture or colour differences between panels. Open and close all doors, the boot and bonnet to check alignment.
For the full breakdown of all 5 tracked issues with repair costs, see the Mercedes-Benz GLC common problems page.
Based on 322k real DVSA MOT tests, the Mercedes-Benz GLC fails more often than average on several items. The biggest outlier is transmission shaft flexible coupling deteriorated at 171x the fleet average, followed by headlight fault (18x).
When viewing a specific car, check its MOT history for recurring advisories in these categories. See the full Mercedes-Benz GLC MOT failure breakdown for data at every mileage point.
Routine servicing (oil and filter change every 15k miles) typically costs £150–£250 at an independent garage.
The bigger-ticket items to budget for include automatic transmission fluid (£300–£500).
See the full Mercedes-Benz GLC service schedule for every interval and cost breakdown.
The Mercedes-Benz GLC is a reasonable used buy provided you check for the issues outlined above. None of the problems we track are insurmountable, but they do reward buyers who inspect thoroughly and verify the service history before committing. 2017-2019 first-generation models offer the best balance of proven reliability and depreciation. These years consistently show MOT pass rates above 91%, well above the model's median. Avoid 2015-2016 early production cars and the 2021 model year. The GLC 220d is the UK sweet spot for diesel economy; the GLC 300 petrol suits lower-mileage drivers. The 2022 facelift improved the infotainment but prices remain high.
Before committing, check the car's full MOT history, verify the service record is complete, and if possible arrange a specialist inspection. Enter any registration into our free report to see the complete picture.
Get Car Wise maintains a database of known mechanical issues for every popular car on UK roads, tracking the faults that owners, specialists and DVSA data reveal.
When you run a report on a specific Mercedes-Benz GLC, we cross-reference the exact variant, engine and age against our database of 5 known issues. Combined with full MOT history analysis, mileage verification and DVLA data, you get a complete picture before viewing.
Enter the registration for MOT history, mileage verification, known faults for that exact variant, and a Get Car Wise Score.
This guide was compiled from independent expert reviews, DVSA MOT data, specialist workshops and our own database of 5 known Mercedes-Benz GLC issues. We are not affiliated with any source listed.