The MOT Files

Section 5 · Axles, wheels, tyres and suspension

5.1.2 Stub axles

Manual indexed

Quick answer

Sub-section 5.1.2 of the MOT inspection manual covers stub axles and lists 7 defects, 4 of them Dangerous. A reference like "(5.1.2 (a))" on a certificate points to the matching row below. The most recorded is "A stub axle swivel pin and/or bush excessively worn", about 0.5 times per 100 failed tests.

Official wording

The defect clauses

  1. 5.1.2 (a)Dangerous

    A stub axle fractured

  2. 5.1.2 (b)(i)Major0.5 per 100 fails

    A stub axle swivel pin and/or bush excessively worn

    Ball joint worn explained: what it means and what puts it right

  3. 5.1.2 (b)(ii)Dangerous

    A stub axle swivel pin and/or bush is so excessive the stub axle is likely to become insecure or directional stability is impaired

    Ball joint worn explained: what it means and what puts it right

  4. 5.1.2 (c)(i)Major

    Movement between the stub axle and axle beam is excessive

  5. 5.1.2 (c)(ii)Dangerous

    Movement between the stub axle and axle beam insecure or directional stability is impaired

  6. 5.1.2 (d)(i)Majorunder 0.1 per 100 fails

    A king pin loose in the axle beam

    Ball joint worn explained: what it means and what puts it right

  7. 5.1.2 (d)(ii)Dangerousunder 0.1 per 100 fails

    A king pin so loose it is likely to affect directional stability

    Ball joint worn explained: what it means and what puts it right

Wording and categories reproduced from the DVSA inspection manual under the Open Government Licence. Frequencies are items per 100 failed class 4 tests across the DVSA anonymised MOT dataset; a clause with no figure was not recorded often enough to appear in any model’s top forty failure items. 4 of 7 clauses link to our own explanation.

Grading

What the categories mean

Dangerous
a direct and immediate risk to road safety or the environment. The vehicle fails and must not be driven until repaired, even to a garage.
Major
a defect that affects safety, the environment or other road users. The vehicle fails.
Minor
a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes.

The full guide to defect grading

Section 5

Other sub-sections of axles, wheels, tyres and suspension

All sections of the manual

Common questions

What does 5.1.2 mean on an MOT certificate?
It refers to sub-section 5.1.2 of the MOT inspection manual, "Stub axles", within section 5, axles, wheels, tyres and suspension. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 7 listed here. 4 of them are graded Dangerous, 3 Major and 0 Minor.
Which stub axles defect is recorded most often?
"A stub axle swivel pin and/or bush excessively worn" (5.1.2 (b)(i)), recorded about 0.5 times per 100 failed MOT tests nationally. We explain what it means and what puts it right.
Does a Minor defect fail the MOT?
No. a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Major and Dangerous defects fail. A Dangerous defect also means the car must not be driven until it is repaired.