Drive shaft CV boot split or damaged
How it can appear on an MOT certificate
- “Drive shaft joint constant velocity boot damaged but preventing the ingress of dirt”
- “Drive shaft joint constant velocity boot split”
- “Drive shaft joint constant velocity boot missing”
What it is
The constant velocity (CV) joints let the drive shafts turn the front wheels while they steer and move up and down. Rubber boots keep the grease in and dirt out.
Why it matters
A split boot loses grease and lets in dirt, and the joint then wears quickly. A worn CV joint often clicks when turning sharply.
What to check when viewing a car
On a test drive, turn on full lock at low speed and listen for clicking. Look behind the front wheels for grease flung around the area.
Has the car you're looking at had this before?
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What the MOT categories mean
- Dangerous
- A direct and immediate risk to road safety, or a serious impact on the environment. The car fails and shouldn't be driven until it's repaired.
- Major
- It may affect the car's safety, put other road users at risk or harm the environment. The car fails and should be repaired straight away.
- Minor
- No significant effect on safety or the environment. The car passes, but it should be repaired as soon as possible.
- Advisory
- Something to keep an eye on that could need repairing in future. The car passes.
Related: seat belts, warning lights and other checks
- Seat belt damaged or not working
- Airbag (SRS) warning light on
- Horn not working
- Oil leak
- Fuel leak
- Battery insecure or leaking
Buying a used car?
General information about this type of MOT defect, not advice about a particular car. How serious it is depends on the car; have any car you're buying inspected by a qualified mechanic.