Mercedes S320 CDI Auto (2006)
2006 Mercedes S320 CDI Auto
CarHunch analysed 116 real MOT records for the 2006 Mercedes S320 CDI Auto. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.
This 2006 S320 CDI has a serious reliability problem: only 28.7% pass their MOT first time, compared to the UK average of 80%. The diesel engines are equally troublesome at 28.5%, so fuel type offers no refuge here.
These cars are typically running around 126,000 miles, which is reasonable for a 2006, but the average 0.53 failures per vehicle suggests systemic issues rather than random wear—likely expensive transmission, suspension, or emissions-related faults that accumulate on these ageing Mercedes. Before buying one, get a pre-purchase inspection from a specialist diesel mechanic, because the MOT data confirms these are high-maintenance cars that will regularly surprise you with repair bills.
What to check before buying a 2006 Mercedes S320 CDI Auto
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 S320 CDI Auto
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 (99%) | 115 | 28.6% | 0.53 |
| Gas Bi-Fuel (1%) | 1 | 50% | 1 |
Mileage Distribution
Most 2006 Mercedes S320 CDI Auto 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.
Half of all 2006 Mercedes S320 CDI Auto vehicles fall between 109,821 and 148,253 miles.
2006 Mercedes S320 CDI Auto — Still on the Road
Numbers are declining — 10 vehicles still getting MOTs in 2025 (26% of peak).
Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2018–2025.
MOT History Averages
Found a specific Mercedes S320 CDI Auto?
Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.
Other model years — Mercedes S320 CDI Auto: