The MOT Files

Suspension

How long do coil springs last?

Data updated

Quick answer

Across every car tested in Britain, coil springs fail the MOT at 0.2 per 100 tests at three to five years old and 4.5 at 12 to 14 years — 20 times the rate. Failures reach half their peak from 9 to 11 years, which is when to have them checked. Springs fatigue and corrode where the coating chips, then snap, often at the bottom coil; potholes and salt accelerate it.

Per 100 MOT tests

Coil springs: failures and advisories by car age

FailuresAdvisories
3–5 yrsreg. 2020–2022
0.2
0.1
6–8 yrsreg. 2017–2019
1.5
0.8
9–11 yrsreg. 2014–2016
3.2
3.8
12–14 yrsreg. 2011–2013
4.5
8.6
15+ yrsreg. 2010 and earlier
3.7
12.5

Items recorded per 100 class 4 tests at each age, across the whole fleet. Advisories run ahead of failures: the tester saw the part wearing and said so a year or two before it failed. Peak band highlighted.

DVSA recorded wording

What the tester writes

When it fails

The defects behind it, explained

Suspension

Other parts in the same system

Every part, every age

Common questions

How long do coil springs last?
Across the British fleet, coil springs barely fail before 9 to 11 years: 0.2 failures per 100 tests at three to five years, rising to 4.5 at 12 to 14 years, 20 times the rate. Springs fatigue and corrode where the coating chips, then snap, often at the bottom coil; potholes and salt accelerate it.
At what age should I have coil springs checked?
From about 9 to 11 years, when failures reach half their peak rate across the fleet. Advisories for coil springs run ahead of failures by a year or two, so a car whose MOT history shows one is on the curve.
Is a worn coil spring an MOT failure?
It depends on how worn. "Road spring broken or fractured" and "Road spring seat or suspension turret corroded" are the defects testers record; each page explains the threshold at which the item fails rather than being advised.

Analysis built from DVSA data of