MOT advisory · manual section 5.3.3

Sub-frame corroded but not seriously weakened

What this MOT advisory 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 an advisory, per 100 MOTs (n=130,233,413)1.89

Most often at17 years

Times recorded2,462,203

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 an advisory: the car passes its MOT, and the tester is warning about the part. An advisory is something the tester noticed that could become a defect later. The car passes its MOT. The advice is to monitor the part and repair it if it gets worse.

When it gets worse, the tester records it as a fail: Sub-frame corroded and seriously weakened.

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 tester fails the car when the part reaches the point the MOT inspection manual describes (section 5.3.3):

A suspension component excessively damaged or corroded

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
Advisory	Sub-frame	corroded but not seriously weakened (5.3.3)	2,462,203

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 17 years: 5.32 per 100 MOTs (n=4,040,458 tests at that age).

Per 100 MOT tests of cars at each age, all makes. We show no figure below 20 tests.
Age	Advisory per 100	Tests (n)
3 years	0.001	8,016,463
4 years	0.006	8,699,937
5 years	0.019	9,425,360
6 years	0.060	10,382,720
7 years	0.16	10,537,318
8 years	0.38	10,440,457
9 years	0.79	9,949,012
10 years	1.38	9,049,507
11 years	2.12	8,087,514
12 years	2.98	7,303,151
13 years	3.81	6,612,160
14 years	4.51	6,054,526
15 years	5.03	5,591,675
16 years	5.26	4,858,625
17 years	5.32	4,040,458
18 years	5.26	3,261,622
19 years	4.96	2,479,858
20 years	4.76	1,845,952
21 years	4.45	1,321,417
22 years	4.20	913,980
23 years	3.86	619,531
24 years	3.33	428,815
25 years	2.87	313,355

Models that get it most

Each model generation is compared with cars of the same ages and fuel, so older and diesel models are not penalised for their age or fuel. Generations are never pooled.

Model generations with the highest rate as an advisory, against cars of the same ages and fuel. A model’s figure counts this defect only at ages where it is among that model’s 25 most recorded items, and as zero elsewhere, so it is a floor. Tests (n) are all the generation’s MOT tests at ages with at least 1,000 tests each; at least 5,000 in total.
Model	Per 100 MOTs, at least	Same ages and fuel	Times as often	Tests (n)	Ages
MG ZSfirst used 2017 or laterMG ZS suspension problems	0.45	0.020	21.9	143,170	3 to 7
MG 3	3.02	0.30	10.0	81,125	3 to 11
MG 6MG 6 suspension problems	5.77	1.26	4.5	5,526	8 to 11
Infiniti Q50Infiniti Q50 suspension problems	1.59	0.45	3.5	8,734	6 to 10
Suzuki BalenoSuzuki Baleno suspension problems	0.62	0.19	3.3	26,797	3 to 9
Mazda 6Mazda 6 suspension problems	6.88	2.06	3.3	259,157	3 to 20
Mazda 3Mazda 3 suspension problems	7.26	2.19	3.3	435,738	3 to 20
Vauxhall AdamVauxhall Adam suspension problems	2.57	0.79	3.2	237,726	3 to 12
Mitsubishi ASXMitsubishi ASX suspension problems	3.65	1.13	3.2	116,909	3 to 15
SsangYong Rodius	0.74	0.24	3.0	8,586	5 to 9
Mitsubishi OutlanderMitsubishi Outlander suspension problems	2.26	0.74	3.0	305,188	3 to 18
Land Rover Discovery SportLand Rover Discovery Sport suspension problems	0.55	0.19	2.9	447,155	3 to 10
Jaguar XFJaguar XF suspension problems	5.59	1.93	2.8	399,683	3 to 17
Citroen C3 PicassoCitroen C3 Picasso suspension problems	0.70	0.24	2.8	22,583	5 to 9
Vauxhall InsigniaVauxhall Insignia suspension problems	4.47	1.57	2.8	834,880	3 to 16
Mazda 5Mazda 5 suspension problems	11.1	3.91	2.8	44,929	8 to 18
Jeep PatriotJeep Patriot suspension problems	12.0	4.52	2.6	8,210	12 to 16
Jeep Compassfirst used before 2017Jeep Compass suspension problems	6.15	2.33	2.6	9,223	9 to 13
Citroen C-CrosserCitroen C-Crosser suspension problems	12.6	4.90	2.5	6,100	13 to 16
Suzuki Celerio	0.90	0.36	2.4	110,627	3 to 10

Read this with care. A fail rate is not a measure of build quality. How far cars are driven, how they are used and how well owners maintain them all change it, and wear items such as tyres and brake pads are common fails. Compare a model only with cars of the same age. Methodology and limits.

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
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
Shock absorber has a serious fluid leak0.86 per 100

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

Buying a used car?

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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