Mercedes G400 MOT Pass Rate
Overall pass rate across all manufacture years, based on 85 real MOT test results. Failure rate: 29.4%.
Data from official DVSA MOT testing records
Mercedes G400 MOT Reliability Overview
The Mercedes G400 is a rare vehicle in the UK, with 85 MOT test results recorded in our database spanning 1 manufacture years. It has an overall MOT pass rate of 70.6% and a failure rate of 29.4%, which is above the UK average of approximately 37%.
Based on this data, the Mercedes G400 earns a "Very Good" reliability rating. The average Mercedes G400 presents for MOT with approximately 118,210 miles on the clock. The 2002 manufacture year performs best with a 67.5% pass rate.
The most common MOT failure for the Mercedes G400 is Lamps, Reflectors and Electrical Equipment, affecting 41.2% of all tests. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. The second most common issue is Brakes at 22.4%. Suspension rounds out the top three at 22.4%. Together, these top 3 failure categories account for a significant portion of all MOT failures for this model.
Top failures across all manufacture years combined. Individual year pages may show different top failures.
What Fails Most
Pass Rate by Manufacture Year
* High Fail Rate badge indicates an MOT pass rate below 65% (failure rate above 35%).
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Lamps, Reflectors And Electrical Equipment | 47.1% | 40 |
| 2 | Suspension | 23.5% | 20 |
| 3 | Brakes | 22.4% | 19 |
| 4 | Steering | 11.8% | 10 |
| 5 | Driver's View Of The Road | 4.7% | 4 |
| 6 | Exhaust, Fuel And Emissions | 4.7% | 4 |
| 7 | Registration Plates And Vin | 3.5% | 3 |
| 8 | Seat Belts And Supplementary Restraint Systems | 3.5% | 3 |
| 9 | Tyres | 3.5% | 3 |
| 10 | Non-component Advisories | 3.5% | 3 |
| 11 | Body, Structure And General Items | 2.4% | 2 |
| 12 | Body, Chassis, Structure | 1.2% | 1 |
| 13 | Noise, Emissions And Leaks | 1.2% | 1 |
Failures per 10,000 Miles
avg. 118,210 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Lamps & Electrical | 3.98 | 47.1% | 40 |
| Suspension | 1.99 | 23.5% | 20 |
| Brakes | 1.89 | 22.4% | 19 |
| Steering | 1.00 | 11.8% | 10 |
| Visibility | 0.40 | 4.7% | 4 |
| Emissions & Exhaust | 0.40 | 4.7% | 4 |
| Body & Structure | 0.30 | 3.6% | 3 |
| Registration Plates and VIN | 0.30 | 3.5% | 3 |
| Seat Belts | 0.30 | 3.5% | 3 |
| Tyres | 0.30 | 3.5% | 3 |
| Non-component advisories | 0.30 | 3.5% | 3 |
| Noise, emissions and leaks | 0.10 | 1.2% | 1 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Mercedes G400 has 118,210 miles when tested for MOT.
📊 Mileage-Adjusted Failure Rate
How often this car fails MOT relative to how much it's driven — a fairer comparison than raw pass rate.
The Mercedes G400 has a mileage-adjusted failure rate of 2.49% per 10,000 miles driven. The average across all makes is 5.38%, so this model is better than average.
About Mercedes G400 MOT Data
The Mercedes G400 is a rare vehicle in the UK, with 85 MOT test results recorded in our database spanning 1 manufacture years. It has an overall MOT pass rate of 70.6% and a failure rate of 29.4%, which is above the UK average of approximately 37%.
For Mercedes G400 owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on lamps, reflectors and electrical equipment and brakes for the best chance of a first-time pass. Use our detailed year-by-year breakdown and failure analysis below to understand how your specific G400 is likely to perform.
Lamps, Reflectors and Electrical Equipment — 41.2% of failures
Lamps, Reflectors and Electrical Equipment issues account for 41.2% of MOT failures on the Mercedes G400. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. Typical repair costs: £5–50. Pre-MOT check: Walk around the car and check every light — headlights (dipped and main beam), side lights, tail lights, brake lights, indicators, hazard lights, reverse light, rear fog light, and number plate lights. Replace any blown bulbs before the test.
Brakes — 22.4% of failures
Brakes issues account for 22.4% of MOT failures on the Mercedes G400. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. Typical repair costs: £150–400. Pre-MOT check: Listen for squealing or grinding noises. Check brake pedal feel — if it feels spongy or goes to the floor, have the system inspected immediately. Look at brake pad thickness through the wheel spokes (minimum 3mm).
Suspension — 22.4% of failures
Suspension issues account for 22.4% of MOT failures on the Mercedes G400. Suspension failures typically involve worn bushes, leaking shock absorbers, broken coil springs, and damaged suspension arms. These affect ride quality, tyre wear, and road holding. Typical repair costs: £200–500. Pre-MOT check: Look for uneven tyre wear, listen for clunking over bumps, and check if the car pulls to one side. A bouncy ride suggests worn shock absorbers. Visually inspect coil springs for cracks.
Frequently Asked Questions
What is the MOT pass rate for the Mercedes G400?
Based on 85 (based on limited data) MOT tests in our database, the Mercedes G400 has an overall pass rate of 70.6% (29.4% fail rate).
What are the most common MOT failures on a Mercedes G400?
The top 3 reasons a Mercedes G400 fails its MOT are: 1. Lamps, Reflectors and Electrical Equipment (41.2%), 2. Brakes (22.4%), 3. Suspension (22.4%). Check these areas before booking your MOT.
Is the Mercedes G400 reliable?
With a 29.4% MOT failure rate, the G400 is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Mercedes G400?
Based on failure data, focus on: Lamps, Reflectors and Electrical Equipment (41.2%); Brakes (22.4%); Suspension (22.4%). These are the areas most likely to cause a fail. Also check all lights, tyres (minimum 1.6mm tread), and windscreen condition — these are quick wins that apply to all cars.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.