What year Mercedes 300 D Diesel Auto is most reliable?

Based on MOT first-test pass rates, the 1989 Mercedes 300 D Diesel Auto has the highest pass rate at 100.0%, out of 180 vehicles tested.

What are the most common Mercedes 300 D Diesel Auto MOT failures?

The most common Mercedes 300 D Diesel Auto MOT failures vary by year. Check the individual year pages for detailed defect breakdowns — links in the table above.

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Mercedes 300 D Diesel Auto — Reliability by Year

673 vehicles · MOT data 1986–1989 · first-test pass rates

This page shows MOT first-test pass rates for each year the Mercedes 300 D Diesel Auto was manufactured — click any year to explore that cohort in detail. Trying to decide which year to buy? See the full buying guide →

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Best pass rate year

1989

100.0% pass rate · 180 vehicles

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Lowest pass rate year

1988

83.3% pass rate · 151 vehicles

Year	Pass rate	Avg mileage	Vehicles
1989	100.0%	272,321 mi	180
1988	83.3%	234,673 mi	151
1987	—	—	148
1986	—	—	194

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