MOT defects · Suspension and steering

Steering ball joint dust cover split MOT minor defect: what it means and which cars get it

In DVSA MOT data for 2023, analysed by RegTail, testers recorded this as a minor defect on at least 0.4 in 100 and as a failure on at least 0.08 in 100 initial MOT tests. The Vauxhall Adam got it most often: recorded 7.2 times per 100 of its 59,564 tests.

DVSA wording: Steering rack gaiter or ball joint dust cover damaged or deteriorated; Steering rack gaiter or ball joint dust cover missing or no longer prevents the ingress of dirt etc.

Failures

0.08 in 100

At least 26,369 tests in 2023

Minor defects

0.4 in 100

At least 123,918 tests in 2023

Most often

Vauxhall Adam

7.2 per 100 tests

What it means

The rubber boot on a steering ball joint has split or perished. Without it, water and dirt get into the joint and wear it out.

How serious it is

Damaged or deteriorated is a minor defect, which passes. Missing or no longer keeping dirt out is a major defect, a fail.

Source: MOT inspection manual for cars and light vans, section 2.1.3.

Major Fail
It may affect the vehicle's safety, put other road users at risk or have an impact on the environment. Repair it immediately.
Minor Pass
No significant effect on the safety of the vehicle or impact on the environment. Repair as soon as possible.

What fixing it usually involves

Usually a new track rod end, with the alignment reset afterwards.

A general guide, not a quote: ask a garage to inspect the car.

Which models get it most

Per 100 initial MOT tests on each model, among the 30 models with at least 20,000 tests where it is among the 40 most common items. DVSA MOT data for 2023, analysed by RegTail.

Model	Tests	Fail	Minor
Vauxhall Adam	59,564	0.7	6.5
Volkswagen Beetle	48,614	2.2	3.7
Fiat 500X	33,176	1.8	4.0
Vauxhall Corsa	948,473	1.7	3.5
Jeep Renegade	26,846	1.6	3.6
Mitsubishi Colt	25,654	·	4.9
Honda CR-V	204,614	·	4.9
SEAT Ibiza	195,989	1.4	2.3
Honda Civic	299,187	·	3.4
SEAT Arona	39,192	0.4	2.4

What to check at a viewing

On the car
Turn the steering to full lock and look at the boots on the steering joints behind the front wheels for splits.
In the MOT history
If this appears in past results, ask what was done and when, and for the receipt.

Check a specific car

Fleet averages only go so far. Enter the registration to see that car's own MOT history, mileage record and current condition, free.

Questions

What does "Steering ball joint dust cover split" mean on an MOT?

The rubber boot on a steering ball joint has split or perished. Without it, water and dirt get into the joint and wear it out.

Steering ball joint dust cover split: is it an MOT fail?

Damaged or deteriorated is a minor defect, which passes. Missing or no longer keeping dirt out is a major defect, a fail.

Which cars are most likely to get "steering ball joint dust cover split" on an MOT?

In DVSA MOT data for 2023, analysed by RegTail, the models that got it most often were the Vauxhall Adam (7.2 per 100 tests), the Volkswagen Beetle (5.9 per 100 tests), the Fiat 500X (5.9 per 100 tests).

More suspension and steering defects

See every MOT defect we explain or MOT pass rates by model.

Coil spring broken or corroded Shock absorber leaking Shock absorber bush worn Suspension bush worn Suspension ball joint worn Anti-roll bar link worn Anti-roll bar link dust cover split Suspension joint dust cover split Track rod end worn Steering ball joint dust cover split Sub-frame corroded Suspension arm corroded CV joint boot split Wheel bearing play

How these figures are made. We counted the defects recorded at every initial MOT test (not retests) of cars and light vans in Great Britain in 2023 in the DVSA anonymised MOT dataset, 33,842,940 tests in all. Each item counts once per test. A failure is a major or dangerous defect, including one fixed during the test. A model's rate is the share of its tests where the item was recorded.

For each model we keep its 40 most frequent items, so a model where a defect is rarer than that is not listed, and figures for all cars are a floor. Defect names and explanations are ours, checked against the MOT inspection manual; DVSA's own wording is shown under each name.

Contains public sector information licensed under the Open Government Licence v3.0. RegTail's analysis of the DVSA anonymised MOT dataset, 2023 tests.