Mercedes-benz 400 Reliability, MOT Pass Rate & Common Faults
Free Mercedes-benz 400 car check
Is the Mercedes-benz 400 reliable? We analysed 1,322 real MOT tests across 213 vehicles to find out.
Got a specific Mercedes-benz 400? Enter the reg for a free check:
The Mercedes-benz 400 is about average for reliability based on real UK MOT data. Common problems include tyre tread depth below requirements of 1.6mm, brake pipe excessively corroded and windscreen wiper does not clear the windscreen effectively. Here's everything you need to know before buying a used Mercedes-benz 400.
Mercedes-benz 400 Number Plates
Number plates registered to a Mercedes-benz 400. Click on any registration for full vehicle details — including MOT history, mileage records, previous owners and damage history.
Mercedes-benz 400 MOT Pass Rate by Year
How likely is a Mercedes-benz 400 to pass its MOT? Here's the pass rate for each registration year, newest first.
Mercedes-benz 400 Problems — What Goes Wrong?
The most common reasons a Mercedes-benz 400 fails its MOT, ranked by how often they occur. Check for these problems before you buy.
Mercedes-benz 400 Mileage — What's Normal?
How many miles does a typical Mercedes-benz 400 owner drive per year? Use this to check if a car you're looking at has suspiciously low or high mileage.
Mercedes-benz 400 MOT Data by Registration Year
Full breakdown of pass rate and mileage for each year. Use this to compare the Mercedes-benz 400 year you're looking at.
| Year | Tests | Pass Rate | Low Mi. | Typical Mi. | High Mi. |
|---|---|---|---|---|---|
| 1993 | 477 | 74.6% | 90,792 | 119,210 | 154,650 |
| 1992 | 601 | 73.9% | 76,510 | 127,596 | 154,400 |
| 1991 | 84 | 73.8% | 69,443 | 123,478 | 148,850 |
How Long Does a Mercedes-benz 400 Last?
Based on 213 Mercedes-benz 400 vehicles on UK roads.
Mercedes-benz 400 Mileage Distribution
Total mileage recorded across all Mercedes-benz 400 MOT tests. If the car you're looking at is above the 75th percentile, it's done more miles than most.
Best Year to Buy a Used Mercedes-benz 400
Based on MOT pass rates across all registration years with sufficient test data.
74.6% MOT pass rate from 477 tests
73.8% MOT pass rate from 84 tests
The best year to buy a used Mercedes-benz 400 is 1993, which has the highest MOT pass rate at 74.6% across 477 tests. The 1991 model year has the lowest pass rate at 73.8% — if you're looking at one from that year, budget for potential repairs and get a thorough pre-purchase inspection.
How Does the Mercedes-benz 400 Compare?
MOT pass rates compared to similar models. Click any model for the full breakdown.
| Model | Pass Rate | Tests | Typical Mileage | Lifespan |
|---|---|---|---|---|
| Mercedes-benz 400 THIS CAR | 74.7% | 1,322 | 121,189 mi | 35 yrs |
| Mercedes-benz C | 77.6% | 8,031,355 | 77,082 mi | 32 yrs |
| Mercedes-benz E | 79.4% | 4,722,746 | 83,960 mi | 33 yrs |
| Mercedes-benz A-class | 77.6% | 4,204,702 | 57,023 mi | 28 yrs |
| Mazda MX-5 Rf Sport Tech | 93.8% | 1,571 | 15,654 mi | — yrs |
Compared to the Mercedes-benz C (77.6% pass rate) and the Mercedes-benz E (79.4% pass rate), the Mercedes-benz 400 trails behind on MOT reliability.
Found a Mercedes-benz 400 you like?
Run a full vehicle history check on the specific car. See finance, stolen, write-off, mileage and MOT data for that exact vehicle.
Check a specific Mercedes-benz 400Should you buy a used Mercedes-benz 400?
The Mercedes-benz 400 has an overall MOT pass rate of 74.7% across 1,322 real MOT tests — roughly in line with the UK average.
The most common problems on the Mercedes-benz 400 are tyre tread depth below requirements of 1.6mm (72 recorded failures), brake pipe excessively corroded (55), and windscreen wiper does not clear the windscreen effectively (39). These are the faults most likely to cause an MOT failure on this model, so check for them carefully on any test drive or pre-purchase inspection. Many are wear-and-tear items that can be budgeted for, but a car that's already failing on multiple fronts may signal neglected maintenance.
A typical Mercedes-benz 400 owner drives around 3,109 miles per year. If the car you're looking at is significantly above this, expect more wear on suspension, brakes and tyres. If it's well below, the vehicle may have been sitting unused — check for perished rubber, corroded discs and stale fluids.
In terms of longevity, most Mercedes-benz 400 models stay on UK roads for around 35 years — a strong showing that suggests solid build quality and readily available parts. If you're buying one that's already approaching that window, the data suggests it has plenty of life left provided it's been maintained.
Before committing to a purchase, we recommend running a full vehicle history check on the specific car. This will reveal any outstanding finance, stolen markers, write-off history and mileage discrepancies that the seller may not disclose — and that the MOT data alone can't tell you.