Used car guide

2021 Ford Mustang: common problems and what to check

What gets flagged at MOT on 2021 Ford Mustangs, from 3,119 tests in 2025, plus known faults and what to look at before you buy one.

3,119MOT tests in 2025
90%pass first time (all 2021 cars: 87%)
8,700typical miles a year
26%had tyres flagged

What gets flagged at MOT

The share of 2021 Ford Mustang MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    26% 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
    6% 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.

  • Wipers, windscreen and mirrors
    3% 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
    3% of testsRough price £80–£250

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

  • Suspension
    2% 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
    2% of testsRough price £10–£80

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

Looking at a Ford Mustang?

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Other years

YearMOT testsMost flagged
20225,060Tyres 25%
20201,073Tyres 22%
20191,226Tyres 19%
20182,115Tyres 23%
20171,873Tyres 23%
20162,533Tyres 24%

Where this comes from: the DVSA's anonymised results for every MOT test in Great Britain in 2025, counting tests of 2021 Ford Mustangs registered in 2021. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score