Suspension Faults Overtake Brakes and Tyres as Major MOT Failure Problem

Suspension problems have emerged as one of Britain’s biggest MOT failure issues, with 4.5 million major and dangerous suspension defects recorded during MOT tests in 2025, new research has revealed.

Freedom of Information data obtained from the Driver and Vehicle Standards Agency (DVSA) by Co-op Insurance shows the number of major and dangerous suspension defects has increased by 10% since 2020.

Co-op’s analysis puts suspension ahead of brakes and tyres as a cause of MOT failure, with the insurer describing it as the leading failure issue identified in its data.

The findings come as Britain’s cars continue to get older and separate RAC figures reveal a substantial increase in breakdowns linked to poor road surfaces.

For garages and MOT Testing Stations, the combination of an ageing vehicle parc, deteriorating suspension components and Britain’s continuing pothole problem could make suspension inspection and repair an increasingly important part of workshop business.

4.5 million major and dangerous suspension defects recorded

According to Co-op Insurance’s analysis of DVSA data, 4.5 million major and dangerous suspension defects were recorded during MOT tests in 2025.

That represents a 10% increase compared with 2020.

The research covered a year in which 42,515,983 MOT tests were recorded, with 7,576,269 vehicles failing their first test.

Co-op says suspension has moved ahead of brakes and tyres in its analysis, representing a change from 2021 and 2022 when brakes and tyres were reported as the most common dangerous defects.

The insurer says suspension was ahead of both categories in 2024 and 2025.

However, there is an important distinction when interpreting the figures.

DVSA’s separately published MOT defect-category data continues to show lamps, reflectors and electrical equipment as the largest overall defect category for Class 3 and 4 vehicles.

For the 2025/26 financial year, lamps and electrical equipment appeared in 10.44% of initial tests, compared with suspension at 8.90%, brakes at 6.10% and tyres at 6.23%.

So while the new research demonstrates that suspension has become a particularly significant cause of MOT failure – and is ahead of brakes and tyres – it should not be taken to mean lighting and electrical defects have disappeared as a major MOT issue.

Latest DVSA figures show suspension problem continuing

The most recent DVSA data suggests suspension remains a significant problem.

Between April and June 2026, suspension defects were recorded in 8.21% of initial Class 3 and 4 MOT tests.

That compares with:

• 5.83% for brakes;
• 6.55% for tyres; and
• 9.98% for lamps, reflectors and electrical equipment.

Suspension accounted for 19.47% of all defects recorded during the quarter.

When looking specifically at major defects, suspension represented 22.22% of the total.

That makes suspension a particularly important area for MOT testers and workshops, even if the precise definition of the “number one” MOT failure reason depends on how the data is measured.

Britain’s cars are getting older

One likely contributor is the increasing age of Britain’s vehicle fleet.

Co-op’s analysis found vehicles aged 11 years and older accounted for 61% of MOT failures in 2025, while vehicles between six and 10 years old accounted for another 31%.

That means older vehicles dominate MOT failures.

Separate figures from the Society of Motor Manufacturers and Traders (SMMT) reinforce the ageing-fleet trend.

SMMT’s latest Motorparc data shows a record 45.7% of cars on UK roads are now more than 10 years old, compared with 43.4% in 2024.

The average UK car reached a record 9.7 years old in 2025, up from 9.5 years the year before.

Britain now has 36.68 million cars in use, so the gradual ageing of such a large vehicle population has significant implications for the independent aftermarket.

Suspension components are exposed to years of movement, impacts, road salt, water, corrosion and general wear.

As motorists keep their vehicles for longer, components such as springs, shock absorbers, bushes, joints, arms and mounting points can increasingly require attention.

Pothole-related breakdowns jumped 15%

Vehicle age isn’t the only factor putting suspension systems under pressure.

Britain’s deteriorating roads are another obvious concern.

RAC figures show its patrols attended 26,048 breakdowns in 2025 where poor road surfaces resulted in damaged shock absorbers, broken suspension springs or distorted wheels.

That was a 15% increase from the 22,703 incidents recorded in 2024.

It equates to around 71 pothole-related breakdowns every day.

The situation could get worse.

In September, the RAC warned that the intense heat and UV exposure experienced during the summer of 2026 could make already fragile road surfaces more susceptible to cracking and further pothole formation.

While it would be wrong to attribute the rise in MOT suspension defects solely to potholes, poor road surfaces can clearly contribute to suspension and wheel damage.

Combined with an ageing vehicle fleet, the figures help explain why suspension inspection is becoming increasingly important.

Why suspension faults can be difficult for drivers to spot

Unlike a failed headlamp or visibly worn tyre, suspension deterioration isn’t always obvious to a motorist.

Components can deteriorate gradually and drivers may simply become accustomed to changes in the way their vehicle behaves.

Separate research published earlier this year by HiQ Tyres & Autocare reached a similar conclusion.

A six-week study of MOT failure reports from a sample of HiQ centres found suspension problems in nearly 40% of failed tests.

The company highlighted broken springs and leaking shock absorbers among the problems being found and argued that many suspension defects remain unnoticed because motorists cannot easily inspect the components themselves.

There are nevertheless warning signs drivers can look out for.

These can include knocking or clunking noises over bumps, excessive bouncing, changes in handling, uneven tyre wear, the vehicle sitting lower on one corner or changes in how it behaves when braking and cornering.

Any noticeable deterioration should prompt an inspection rather than simply waiting until the next MOT.

What suspension defects can fail an MOT?

DVSA’s current MOT Inspection Manual contains extensive requirements covering suspension systems.

Testers inspect areas including:

• springs;
• shock absorbers;
• suspension arms, rods and struts;
• subframes;
• anti-roll bars;
• suspension joints, pins and bushes;
• gas, air and fluid suspension systems; and
• suspension mounting areas and supporting structures.

A fractured or seriously weakened spring is categorised as a major defect.

If the main leaf of a leaf spring is fractured, the defect is categorised as dangerous.

A shock absorber that is severely leaking or damaged to the extent that it does not function is a major defect, while one that is missing or likely to become detached can be dangerous.

Excessively worn suspension joints, pins, bushes or bearings can also result in failure.

Where a suspension component is fractured or considered likely to fail, DVSA’s manual categorises the defect as dangerous.

The distinction matters because dangerous defects represent the most serious MOT failure category.

Corrosion can also cause suspension failures

It’s not only mechanical wear that testers need to consider.

DVSA specifically warns testers that some suspension components use thin-gauge steel pressings containing hollow sections or upward-facing areas where road dirt, salt and other contaminants can collect.

These can suffer severe localised corrosion.

The MOT also assesses the strength of load-bearing structures around suspension mounting points.

If the structure within 30cm of a spring, subframe or suspension mounting is significantly weakened, it can result in a major failure.

Where it is so badly weakened that control of the vehicle is likely to be adversely affected, the defect becomes dangerous.

This is another reason why older vehicles can present more complicated suspension-related problems than simply replacing a worn shock absorber or bush.

An opportunity for garages before the MOT

For independent garages, the figures demonstrate the value of checking suspension condition as part of routine servicing and pre-MOT inspections.

Suspension is particularly suited to preventative workshop maintenance because many components cannot be properly assessed by a motorist standing next to the vehicle.

Getting a car onto a ramp allows technicians to identify problems such as worn bushes, damaged springs, leaking dampers, excessive joint movement and corrosion before they become more serious.

Garages can also use previous MOT advisories to help identify components that may now require attention.

An advisory relating to suspension wear shouldn’t simply be forgotten because the vehicle passed its previous MOT.

If the vehicle covers another year’s mileage over poor roads, deterioration may continue until that advisory becomes a major or potentially dangerous defect.

MOT testers still need to assess defects correctly

The rise in suspension defects is also relevant to MOT testers themselves.

Suspension can involve judgement when assessing wear, movement and deterioration.

For example, DVSA’s Inspection Manual reminds testers that some rubber and synthetic bushes are designed to allow a relatively high degree of movement.

They should only be rejected where serious deterioration of the bonding or flexible material can be seen.

Similarly, some MacPherson strut top bushes can show significant lateral movement when the suspension is hanging free. DVSA says they should only be rejected where that movement is caused by wear or maladjustment.

Correct defect assessment therefore remains essential.

Suspension could become an even bigger aftermarket opportunity

The wider trends behind the figures are difficult to ignore.

Britain now has a record number of cars on the road, almost half of them are more than a decade old, the average vehicle is getting older and pothole-related breakdowns increased substantially last year.

Against that backdrop, 4.5 million major and dangerous suspension defects were recorded in MOT tests during 2025.

For motorists, the message is to pay attention to changes in handling, noises and previous MOT advisories rather than waiting for components to deteriorate to the point of failure.

For garages, it reinforces the importance of suspension inspection as part of routine servicing and preventative maintenance.

And for MOT testers, it highlights an area of the test where accurate inspection and correct defect categorisation remain particularly important.

With millions of suspension defects already being identified through MOT testing each year, Britain’s ageing vehicle fleet and challenging road conditions suggest suspension will remain a major workshop and MOT issue for some time to come.

External Sources:

Co-op – Original 4.5 million suspension defects research

DVSA – Latest MOT failures by defect category

DVSA – MOT suspension inspection requirements

SMMT – Latest UK vehicle fleet age data

RAC – Pothole-related breakdowns rise 15%

HiQ – Research into suspension-related MOT failures