The picture
635: middle-of-the-pack on first-time pass
Across 2,435 MOT tests, the 635 returns 78.2% first-time pass — roughly in line with the UK fleet average. The single most-logged Major fail is worn suspension bushes. A number-plate lamp out and windscreen damage round out the top three. Average tested mileage sits at 121,664, 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 suspension pin, bush or joint excessively worn
90 occurrences · 3.7% of tests
- 02
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
67 occurrences · 2.8% of tests
- 03
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
65 occurrences · 2.7% of tests
- 04
A tyre cords visible or damaged
59 occurrences · 2.4% of tests
- 05
Tyre tread depth not in accordance with the requirements
57 occurrences · 2.3% of tests
- 06
A steering ball joint with excessive wear or free play
55 occurrences · 2.3% of tests
- 07
A suspension joint dust cover missing or no longer prevents the ingress of dirt etc
46 occurrences · 1.9% of tests
- 08
A suspension joint dust cover severely deteriorated
43 occurrences · 1.8% of tests
- 09
A suspension pin, bush or joint excessively worn
40 occurrences · 1.6% of tests
- 10
Parking brake efficiency below minimum requirement
37 occurrences · 1.5% 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 4 failures
£208–£465
If every one of this 635'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.
Item 01 · Amazon UK
H7 / W21W bulb pack
A spare-bulb kit lives in the boot. Test morning is not the time to find your stop-lamp's gone.
Search Amazon UK
Item 02 · Amazon UK
Digital tyre-tread depth gauge
Five quid for a gauge beats £150 for a retest. UK MOT minimum is 1.6mm — most testers fail anything below 2mm to be safe.
Search Amazon UK
Buying or keeping a 635?
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 635 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.