BMW 6 Series common problems and MOT failures
What goes wrong on a used BMW 6 Series, year by year: known faults from UK buying guides, the parts flagged at MOT more than on other cars (from 14,747 MOTs done during 2023–2025), and what to check before you buy one.
The 1978 BMW 6 Series
Our MOT figures start with cars first registered in 1990. There are no known faults on record for this year in the UK buying guides we use, so the rest of this page covers the BMW 6 Series as a whole.
What to check on a 1978 car
- Rust and structure
Look underneath at the sills, floor, chassis rails and jacking points. Rust in the structure costs far more to fix than paint bubbles.
- MOT-exempt isn’t roadworthy
Cars over 40 don’t need an MOT, but they must still be safe. A voluntary MOT or a specialist inspection is worth the money.
- Paperwork
Old MOT certificates, bills and restoration photos show how it has been looked after. Check the logbook matches the car’s VIN and engine number.
- Originality
Changes from standard affect value and insurance. Ask what has been replaced or modified.
- Insurance
Classic insurance is often cheaper but may limit mileage and use. Get a quote before you buy.
Other years
Most years have their own guide. The year is when the car was first registered (it’s on the logbook, or check the reg below).
202620202019201820172016201520142013201220112010200920082007200620052004200319901989198819871986198519841983198219811980197919781977
What usually goes wrong with a BMW 6 Series?
We haven’t found widely reported faults for the BMW 6 Series in the UK buying guides we use yet. That doesn’t mean it has none, so check the car carefully and look at the MOT weak spots below.
Common BMW 6 Series MOT failures to check
Parts flagged at MOT well above the usual rate for cars the same age, for each fuel on its own. From the DVSA’s results for every MOT done in Great Britain during 2023–2025.
Petrol
Flexible couplings
up to 0× usualStands out on cars registered in 2018.
Rough price £150–£1,000 our estimateAt the viewing: Check the sills, wheel arches and underneath for rust, and look along the panels for uneven gaps or paint.
Diesel
Flexible couplings
up to 49× usualStands out on cars registered in 2017, 2018 and 2019.
Rough price £150–£1,000 our estimateAt the viewing: Check the sills, wheel arches and underneath for rust, and look along the panels for uneven gaps or paint.
Drive shaft (CV) joints
up to 7× usualStands out on cars registered in 2017 and 2018.
Rough price £60–£350 our estimateAt the viewing: Drive slowly on full steering lock in both directions and listen for clicking. Look for split rubber boots behind the front wheels.
BMW 6 Series MOT pass rate by year
Of the years since 2005 with plenty of MOT tests, the 2012 BMW 6 Series did best (80% passed first time, 16 points above all 2012 cars) and the 2020 did worst (89%, 2 points above all 2020 cars). Older cars fail more, so compare each year with all cars registered the same year.
| Year | Pass first time | All cars that year | MOT tests |
|---|---|---|---|
| 2020 | 89% | 87% +2 | 730 |
| 2019 | 89% | 85% +4 | 3,162 |
| 2018 | 88% | 83% +5 | 4,905 |
| 2017 | 85% | 80% +5 | 767 |
| 2013 | 79% | 67% +12 | 2,110 |
| 2012 | 80% | 64% +16 | 1,554 |
| 2011 | 79% | 62% +17 | 229 (small sample) |
| 2009 | 78% | 59% +19 | 149 (small sample) |
| 2008 | 72% | 57% +15 | 248 (small sample) |
| 2007 | 72% | 57% +15 | 254 (small sample) |
| 2006 | 71% | 56% +15 | 427 (small sample) |
| 2005 | 73% | 57% +16 | 212 (small sample) |
Questions to ask the seller before buying a BMW 6 Series
Ask before you travel to see it. A seller who knows the car will have answers, and receipts.
- Any recent work on the flexible couplings? (Flagged at MOT 50× as often on the BMW 6 Series as on other cars the same age.)
- Any recent work on the drive shaft (cv) joints? (Flagged at MOT 6.5× as often on the BMW 6 Series as on other cars the same age.)
- Can I see the service history and receipts for any big jobs?
Looking at a BMW 6 Series?
Check the actual car: its own MOT history, whether it already shows these weak spots and what to ask the seller. Free, no sign-up.
Where this comes from: MOT figures are the DVSA’s anonymised results for every MOT test done in Great Britain during 2023–2025, grouped by the year each car was first registered. How many are on the road is from the Department for Transport’s vehicle licensing statistics. Known faults are from UK buying guides, in our own words, with links. How we score