Mercedes-Benz R-Class MOT pass rate and common problems
81.4% of 4,406 Mercedes-Benz R-Class MOT tests pass.
At 81.4%, the R-Class passes slightly less often than the average across all Mercedes-Benz models (83.5%).
The Mercedes-Benz R-Class has a pass rate of 81.4%, a little higher than the national average for cars (79.2%).
Own this Mercedes-Benz R-Class?
This is the average across every Mercedes-Benz R-Class in the dataset. Look up your own registration for its actual MOT history, and a free place to keep its maintenance records.
Have service invoices? Upload and keep them with your car’s history →
How to check and keep your Mercedes-Benz’s service history →
Pass rate by vehicle age
Pass rate declines noticeably with age, from 84.7% at 10–15 years to 75.9% at 15+ years.
| Vehicle age | Pass rate | Tests | Average mileage |
|---|---|---|---|
| 0–3 years | no tests recorded | 0 | no reading |
| 3–6 years | no tests recorded | 0 | no reading |
| 6–10 years | no tests recorded | 0 | no reading |
| 10–15 years | 84.7% | 2,762 | 106,876 miles |
| 15+ years | 75.9% | 1,644 | 125,162 miles |
Common MOT failure reasons for the Mercedes-Benz R-Class
The most common reason the Mercedes-Benz R-Class fails its MOT is brakes — present in 48.8% of failed tests, most often logged as "Efficiency below requirements".
| Category | Share of failed tests | Example |
|---|---|---|
| Brakes | 48.8% | Efficiency below requirements |
| Lamps, reflectors and electrical equipment | 45.5% | Not working |
| Tyres | 17.4% | Tread depth below requirements of 1.6mm |
| Body, chassis, structure | 17.4% | Constant velocity boot split or insecure, no longer prevents the ingress of dirt |
| Noise, emissions and leaks | 17.4% | Inoperative or indicates a malfunction |
| Suspension | 14.4% | Has a serious fluid leak |
| Visibility | 8.0% | Does not clear the windscreen effectively |
| Seat belts and supplementary restraint systems | 4.4% | Warning lamp indicates a fault |
| Steering | 3.5% | Gaiter missing or no longer prevents the ingress of dirt |
| Road Wheels | 2.1% | Fixing missing |
Buying a used Mercedes-Benz R-Class: what to check
These checks follow the Mercedes-Benz R-Class’s own MOT record: the areas it fails on most often, and how that changes as the car gets older. None of them replaces a mechanic’s inspection, but they tell you where to look first.
The biggest drop in pass rate for the Mercedes-Benz R-Class comes between 10–15 years and 15+ years old, from 84.7% to 75.9%. If you are looking at one in or just past that range, read its MOT history closely.
By mileage, the steepest fall is from 90,000–120,000 mi to 120,000+ mi: 88.1% down to 73.4%. Mileage matters as well as age, so compare the car’s recorded mileages with its year.
1. Brakes
Recorded in 48.8% of failed Mercedes-Benz R-Class MOTs. 17.2% of tests at 15+ years failed on brakes, against 8.0% at 10–15 years.
On the test drive, the car should stop straight without pulling or juddering, and the handbrake should hold it on a slope. Look through the wheels for scored or heavily lipped discs.
2. Lights and electrics
Recorded in 45.5% of failed Mercedes-Benz R-Class MOTs. 16.3% of tests at 15+ years failed on lights and electrics, against 7.3% at 10–15 years.
Walk round with the lights on: headlights (dipped and main), indicators, brake lights, fog light and number-plate lamp. Check the dashboard warning lights come on with the ignition, then go out once the engine starts.
3. Tyres
Recorded in 17.4% of failed Mercedes-Benz R-Class MOTs.
Check tread depth across the whole width of every tyre, including the inner edge. Uneven wear can point to alignment or suspension problems. Look for cuts and bulges in the sidewalls.
4. Bodywork and corrosion
Recorded in 17.4% of failed Mercedes-Benz R-Class MOTs.
Look underneath and along the sills for corrosion, especially near suspension and seat-belt mountings. Uneven panel gaps or mismatched paint can indicate accident repair.
5. Exhaust, emissions and leaks
Recorded in 17.4% of failed Mercedes-Benz R-Class MOTs. 6.1% of tests at 15+ years failed on exhaust, emissions and leaks, against 2.9% at 10–15 years.
Look under the car for fresh oil or coolant, and listen for blows or rattles from the exhaust. Watch for smoke from the tailpipe when the engine starts and when you accelerate.
Check the car’s own MOT history. Averages describe the model, not the car in front of you. Look up its registration for past failures, advisories that were never fixed, and gaps or dips in the recorded mileage.
Ask for the service history. Invoices show what was done and when; a stamp alone shows less. See how to check Mercedes-Benz service history and what a service history check can tell you.
Related Mercedes-Benz models
- Mercedes-Benz CL — 84.0% pass rate
- Mercedes-Benz GLS — 91.1% pass rate
- Mercedes-Benz GT — 96.6% pass rate
- Mercedes-Benz Citan 109 Pure CDI — 78.4% pass rate
- Mercedes-Benz 500 — 87.0% pass rate
- Mercedes-Benz 230 — 77.9% pass rate
Frequently asked questions
- What is the MOT pass rate for the Mercedes-Benz R-Class?
- 81.4% of Mercedes-Benz R-Class MOT tests pass, based on 4,406 tests in the DVSA anonymised MOT tests and results dataset.
- What are the most common MOT failures for the Mercedes-Benz R-Class?
- The most common reason the Mercedes-Benz R-Class fails its MOT is brakes — present in 48.8% of failed tests, most often logged as "Efficiency below requirements".
- What are the common problems with the Mercedes-Benz R-Class?
- Going by its MOT results, the most common problem areas on the Mercedes-Benz R-Class are brakes; lights and electrics; tyres. 17.2% of tests at 15+ years failed on brakes, against 8.0% at 10–15 years.
- What should I check when buying a used Mercedes-Benz R-Class?
- Start with the areas it most often fails its MOT on: brakes; lights and electrics; tyres; bodywork and corrosion; exhaust, emissions and leaks. Then check the specific car's MOT history by registration for failures, advisories and mileage, and ask the seller for service invoices.
- Does this show the Mercedes-Benz R-Class's service history?
- No — this is MOT test data, which covers roadworthiness, not servicing. A service history is a separate record of maintenance work, which a specific car only has if its owner has kept it. See the Mercedes-Benz service history guide for how to check and keep one.