MOT cost .
BMW 840
MOT 2023
Wikimedia

BMW

840

799 MOT tests analysed. lands in the middle of the pack — here's where 840s pass, fail, and end up on the retest sheet.

That's 3.6 points above the UK fleet average across our 1,988 tracked models — a confident result.

Pass

79.3%

Pass-after-fix

3.8%

Fail

15.9%

Avg miles

107,695

Pass + Pass-after-fix + Fail = 100%

The picture

840: middle-of-the-pack on first-time pass

Across 799 MOT tests, the 840 returns 79.3% first-time pass — roughly in line with the UK fleet average. The single most-logged Major fail is a torn suspension dust cover. Headlamp aim out of spec and windscreen damage round out the top three. Average tested mileage sits at 107,695, 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.

  1. 01

    A suspension joint dust cover severely deteriorated

    62 occurrences · 7.8% of tests

  2. 02

    The aim of a headlamp is not within limits laid down in the requirements

    27 occurrences · 3.4% of tests

  3. 03

    Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view

    23 occurrences · 2.9% of tests

  4. 04

    A suspension joint dust cover missing or no longer prevents the ingress of dirt etc

    23 occurrences · 2.9% of tests

  5. 05

    Wiper blade missing or obviously not clearing the windscreen

    19 occurrences · 2.4% of tests

  6. 06

    Lambda coefficient outside the default limits or the range specified by the manufacturer

    16 occurrences · 2.0% of tests

  7. 07

    Steering rack gaiter or ball joint dust cover damaged or deteriorated

    13 occurrences · 1.6% of tests

  8. 08

    A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources

    12 occurrences · 1.5% of tests

  9. 09

    A suspension pin, bush or joint excessively worn

    12 occurrences · 1.5% of tests

  10. 10

    Windscreen washers not working or not providing sufficient fluid to clear the windscreen

    11 occurrences · 1.4% 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

£190–£605

If every one of this 840'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 →

Try the calculator

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

Headlight restoration kit

Yellowed lenses fail the light-output test. A restoration kit lifts the haze in an afternoon for £20.

Search Amazon UK

Item 02 · Amazon UK

Bosch Aerotwin wiper blades

Cheap wipers fail the test on smear streaks. Bosch Aerotwins last a winter and clear a screen properly.

Search Amazon UK

Buying or keeping a 840?

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 840 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.