MOT fail · manual section 5.3.3

Sub-frame mounting prescribed area excessively damaged significantly reducing structural strength

What this MOT fail means, how often testers record it and what garages charge per hour. From 130,233,413 DVSA MOT tests taken 2022 to 2025.

MOT data updated 28 September 2026

As a fail, per 100 MOTs (n=130,233,413)0.002

Most often at24 years

Times recorded2,345

Times recorded adds every DVSA code with this wording, so a test can record it more than once, for example on two wheels under separate codes.

What it means

This is a major defect: the car fails its MOT. A major defect may affect the car’s safety, put other road users at risk or harm the environment. The car fails its MOT and the defect must be repaired.

Before it reaches this point, testers often record it as an advisory: Sub-frame mounting prescribed area damaged but not considered excessive.

Springs, shock absorbers, arms, bushes and ball joints hold each wheel in place and control how it moves. Wear lets a wheel move in ways it should not, and corrosion can weaken springs and mounting points.

The MOT inspection manual describes the defect (section 5.3.3) as:

The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired

Read this section of the MOT inspection manual on GOV.UK

The DVSA codes counted on this page: the manual item and the defect text as DVSA records them. The heading above joins the two, as a certificate does; the tester also adds the position, such as nearside front.
Result	Manual item	DVSA defect text	Records
Fail Major	Sub-frame mounting prescribed areas	prescribed area excessively damaged significantly reducing structural strength (5.3.3)	2,345

Got an MOT advisory or defect on a certificate? Paste it into the MOT advisory checker to see what it means.

How common it is by age

Testers record it most at 24 years: 0.012 per 100 MOTs (n=428,815 tests at that age).

Per 100 MOT tests of cars at each age, all makes. We show no figure below 20 tests.
Age	Fail per 100	Tests (n)
8 years	0	10,440,457
9 years	0	9,949,012
10 years	0.001	9,049,507
11 years	0.001	8,087,514
12 years	0.002	7,303,151
13 years	0.003	6,612,160
14 years	0.004	6,054,526
15 years	0.005	5,591,675
16 years	0.005	4,858,625
17 years	0.006	4,040,458
18 years	0.007	3,261,622
19 years	0.007	2,479,858
20 years	0.008	1,845,952
21 years	0.008	1,321,417
22 years	0.010	913,980
23 years	0.009	619,531
24 years	0.012	428,815
25 years	0.009	313,355

Repair and cost

We do not map this defect to one repair job, because the fix depends on the cause. Garages charge by the hour, so ask for a quote that lists labour time and parts.

Local garage labour, per hour (65 shops)£78

Local garage, middle half£70 to £96

Main dealer labour, per hour (62 shops)£156

Main dealer, middle half£144 to £174

Median hourly rate charged for car repairs, from 1,058 local garage and 953 main dealer price quotes collected by the ONS, September 2025 to August 2026. The same shops are priced each month, so the number of shops is the real sample.

Related MOT defects

Suspension arm pin or bush worn but not resulting in excessive movement4.92 per 100
Coil spring corroded3.09 per 100
Shock absorber has light misting of oil2.89 per 100
Coil spring fractured or broken2.37 per 100
Sub-frame corroded but not seriously weakened1.89 per 100
Suspension arm ball joint excessively worn1.41 per 100
Suspension arm ball joint has slight play1.31 per 100
Suspension arm pin or bush excessively worn1.19 per 100
Anti-roll bar linkage ball joint has slight play1.18 per 100
Suspension arm corroded but not seriously weakened1.08 per 100

All axles, wheels, tyres and suspension defects All MOT defects Car repair costs

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Source

Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data, class 4 normal MOT tests, 2022 to 2025, and the MOT inspection manual published on GOV.UK. Prices: ONS consumer price inflation price quotes, September 2025 to August 2026, UK.

MOT data updated 28 September 2026. Prices updated 22 September 2026.

Not affiliated with or endorsed by DVSA or the Office for National Statistics. How we calculate these figures · Data sources