The picture
640: above-average pass rates, with caveats
Across 11,829 MOT tests, the 640 returns 83.9% first-time pass — above the UK fleet average. The single most-logged Major fail is a seriously damaged tyre. A broken or weak spring and a tyre with the cords showing round out the top three. Average tested mileage sits at 70,563, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.
Top ten reasons for rejection.
- 01
A tyre seriously damaged
428 occurrences · 3.6% of tests
- 02
A spring or spring component fractured or seriously weakened
344 occurrences · 2.9% of tests
- 03
A tyre cords visible or damaged
307 occurrences · 2.6% of tests
- 04
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
214 occurrences · 1.8% of tests
- 05
Tyre tread depth not in accordance with the requirements
208 occurrences · 1.8% of tests
- 06
A tyre seriously damaged
200 occurrences · 1.7% of tests
- 07
Wiper blade missing or obviously not clearing the windscreen
133 occurrences · 1.1% of tests
- 08
Wiper blade defective
121 occurrences · 1.0% of tests
- 09
Any fracture or welding defect on a wheel
106 occurrences · 0.9% of tests
- 10
Number plate does not conform to the specified requirements
98 occurrences · 0.8% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Worst-case fix budget · top 3 failures
£200–£430
If every one of this 640's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
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Build your own retest budget.
Tools that pre-empt a retest.
Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.
Owner reports · Honest John
What owners actually report.
Verbatim faults logged by owners on honestjohn.co.uk over recent years. We didn't summarise — these are the words people typed in.
What's good
Sleek looks and more handsome than previous 6 Series. Powerful yet economical 640d has an epic engine. Amazingly refined.
Buying or keeping a 640?
Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a 640 and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.