Used car guide

2018 BMW 5 Series diesel: common problems and MOT failures

What MOT testers find on the diesel BMW 5 Series first registered in 2018 (diesel cars only): we looked at the 29,491 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.

29,491MOTs of 2018 diesel cars, done in 2023–2025
87%pass first time (all 2018 cars: 83%)
10,400typical miles a year
3×the usual rate for shock absorbers

What goes wrong more than usual on a 2018 BMW 5 Series diesel?

Parts flagged at MOT more often on the 2018 BMW 5 Series diesel than on all cars registered in 2018.

  • Shock absorbers3× usual
    BMW 5 Series
    7% All 2018 cars
    2.3%

    Failed outright at MOT: 0.9%, against 0.4% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £200–£300 (pair, average rear to front) ClickMechanic

    At the viewing: Push down hard on each corner. It should bounce once and settle. Look for oil on the shock absorber body.

  • Flexible couplingsnull× usual
    BMW 5 Series
    3.2% All 2018 cars
    0%

    Failed outright at MOT: 0.2%, against 0% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £150–£1,000 our estimate

    At the viewing: Check the sills, wheel arches and underneath for rust, and look along the panels for uneven gaps or paint.

Common 2018 BMW 5 Series diesel MOT failures and advisories

The share of 2018 BMW 5 Series diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    24% of testsRough price £70–£150

    At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.

  • Brakes
    10% of testsRough price £150–£350

    At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.

  • Suspension
    8% of testsRough price £120–£400

    At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.

  • Lights and electrics
    6% of testsRough price £10–£80

    At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

  • Wipers, windscreen and mirrors
    4% of testsRough price £15–£250

    At the viewing: Check for chips in the driver's view, and test the wipers and washers.

  • Seats and seatbelts
    2% of testsRough price £80–£250

    At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.

Known faults on the 2018 BMW 5 Series diesel

Reported by owners, mechanics and buying guides for this model and age. Check which engine the car has, as some apply to one engine only.

  • EGR and particulate filter problems (diesel)

    Diesel

    Diesels came last of 20 executive cars in What Car?'s survey, with costly EGR valve and DPF faults and repeat dealer visits. There were also EGR cooler and coolant recalls for fire risk.

    At the viewing: Ask a BMW dealer to check the VIN for recalls, and watch for warning lights.

    Source: What Car?: used BMW 5 Series (2017-2023) reliability

  • Ten recalls

    All engines

    Recalls also covered the brake pedal switch, curtain airbags, the steering gear, a balance shaft bearing, 48-volt battery cables, rear driveshafts and plug-in hybrid batteries.

    At the viewing: Ask a BMW dealer to confirm every recall has been done.

    Source: What Car?: used BMW 5 Series (2017-2023) reliability

  • Electrical and sensor faults

    All engines

    Most petrol faults are electrical, including faulty sensors, persistent warning lights and infotainment faults.

    At the viewing: Test every button and screen, and look for warning lights.

    Source: What Car?: used BMW 5 Series (2017-2023) reliability

Questions to ask the seller before buying a 2018 BMW 5 Series diesel

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

  1. Have the EGR recalls been done, and has it had any EGR or DPF work?
  2. Any recent work on the shock absorbers? (Flagged at MOT 3× as often on the 2018 BMW 5 Series diesel as on other cars the same age.)
  3. Any recent work on the flexible couplings? (Flagged at MOT null× as often on the 2018 BMW 5 Series diesel as on other cars the same age.)
  4. Can I see the service history and receipts for any big jobs?

Looking at a BMW 5 Series?

Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.

Other years

Every year of the BMW 5 Series compared

YearMOT testsMost flagged
2026–Too new for MOT data
2025–Too new for MOT data
2024–Too new for MOT data
2023449Tyres 12%
20222,690Tyres 22%
20213,736Tyres 22%
202012,610Tyres 22%
201946,328Tyres 23%
201739,758Tyres 24%
2016120Tyres 18%
2015188Tyres 19%
2014591Tyres 24%
201317,632Tyres 30%
201217,731Tyres 30%
20113,218Tyres 31%
20101,982Tyres 30%
20092,128Suspension 33%
20082,430Suspension 37%
20072,675Suspension 43%
20062,292Suspension 43%
20051,153Suspension 46%
2004829Suspension 48%
2003630Suspension 39%
2002523Brakes 39%
2001360Suspension 43%
2000232Suspension 41%
1999174Brakes 44%
1998167Brakes 38%
1997–Too few tests
1996–Too few tests
1995–Too few tests
1994–Too few tests
1993–Too few tests
1992–Too few tests
1991–Too few tests
1990–Too few tests
1989–Too few tests
1988–Too few tests
1987–Too few tests
1986–Too few tests
1985–Too few tests
1984–Too few tests
1983–Too few tests
1982–Too few tests
1981–Too few tests
1980–Too few tests
1979–Too few tests
1978–Too few tests
1975–Too few tests

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of BMW 5 Series cars first registered in 2018. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score