MOT advisory: shock absorber has light misting of oil
Shock absorbers are oil-filled dampers that stop the car bouncing after a bump. Their seals wear, and a thin film of oil can appear on the outside. The tester saw a light misting but not a serious leak.
What the tester wrote
| Result | Wording on the certificate | Category |
|---|---|---|
| Advisory | Shock absorbers: has light misting of oil | Advisory (pass) |
| Fail | Shock absorbers: has a serious fluid leak | Major |
What the MOT checks
A shock absorber with a serious fluid leak fails, because a damper that's lost its oil stops doing its job. The manual is clear that slight seepage leaving a film of fluid isn't a reason to fail, so a misted damper passes with this note.
The tester is only looking at the outside of the unit. They don't measure how well it damps.
"Slight seepage causing a film of fluid on a shock absorber is not a reason for rejection."
MOT inspection manual, section 5.3.2 Shock absorbers. Read it on GOV.UK
How common it is
In 2025 this advisory was recorded on 3.1 in every 100 class 4 MOT tests (1,029,490 of 33,210,774 initial tests). The matching fail was recorded on 0.9 in every 100 (289,322 tests).
The typical car with the advisory was 11 years old with 87,821 miles recorded (medians).
| Age at test (years) | Advisory per 100 tests | Fail per 100 tests |
|---|---|---|
| 0-2 | 1.0 | 0.2 |
| 3 | 1.3 | 0.3 |
| 4-5 | 1.8 | 0.3 |
| 6-7 | 2.4 | 0.5 |
| 8-10 | 3.3 | 0.8 |
| 11-14 | 4.1 | 1.3 |
| 15-19 | 4.3 | 1.6 |
| 20+ | 3.1 | 1.0 |
'Not shown' means fewer than 1,000 tests in that cell, or a cell hidden so a small one can't be worked out. Age is years since first registration. First MOTs often happen just before a car's third birthday, so many show as age 2.
Does it turn into a fail at the next MOT?
We followed the same cars to their next MOT, 240 to 500 days later (805,122 pairs where this advisory was recorded). 7.5% failed on the same item at that next test, and another 33.1% had the same advisory again.
Among cars where this item wasn't noted at all, 0.72% failed on it next time. So a car with this advisory was about 10 times as likely to fail on this item as one without it.
These are averages. We can't see what owners did between tests. Some will have fixed the problem, and a fix would stop a fail.
What it usually means for a buyer
A misted damper can carry on for a long time, but a leak tends to grow. On a test drive, notice whether the car keeps bouncing after a speed bump, wallows in bends or dips its nose hard under braking. Uneven, scalloped wear on the tyres is another sign.
Like brakes, dampers are normally replaced in pairs. If the note keeps coming back, budget for both sides of the axle.
Typical fix
Replace the dampers in pairs on the same axle. On many cars the top mounts and bump stops are changed at the same time. Prices vary a lot by car and garage, so get a quote for the specific car.
Questions to ask the seller
You can read any car's MOT history, including advisories, free on GOV.UK. Our MOT advisory decoder explains the other notes in plain English.
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Sources and limitations
- Data: DVSA MOT anonymised test results and test items, class 4 initial tests, 2024 and 2025 (open data on GOV.UK). Same DVSA data as our MOT dataset.
- 'Fail' includes items fixed at the test centre within an hour (pass after rectification).
- An advisory is a tester's judgement on the day. Testers differ, and some problems are not visible at an MOT.
- The MOT is not a service and does not check the engine, clutch or gearbox in depth.
- Counts under 1,000 are not shown. No make or model figures are published here.
Contains public sector information licensed under the Open Government Licence v3.0. Source: Driver and Vehicle Standards Agency (DVSA), MOT Anonymised Data. Analysis by CarCheckHQ. Not endorsed by DVSA.
Written by the CarCheckHQ team.