Could the things that go bump on the road be your vehicle trying to tell you something?
Things That Go Bump on the Road: Strange Vehicle Noises Explained
You almost certainly know the usual sounds of your car, van or motorbike. So when a clunk appears halfway through a familiar journey, it tends to get your attention.
The timing of a noise can help a mechanic find it. Does it happen when you change gear, drive over a bump, brake or turn? The same sound can have several causes, though. If you hear a new knock or rattle that you can’t explain, get the vehicle checked. A current MOT certificate doesn’t guarantee that it remains safe to drive.
A clunk when changing gear or pulling away
This is the sort of noise that can make you think immediately of the gearbox. A worn engine or gearbox mount is one possibility, as the engine and transmission move when power is applied. The clutch or transmission could also need attention.
Listen for a pattern to describe to the garage. Does it happen in every gear, only when pulling away or when you lift off the accelerator? Mention any juddering or difficulty selecting gears too. The clunk alone can’t confirm that a gearbox mount is the cause.
A knock over speed bumps or potholes
If it happens mainly on uneven roads, the suspension is one place a mechanic may look. Worn components or a damaged spring can produce clunks and rattles. A loose exhaust can make a similar noise, which is why a sound from somewhere underneath needs a proper inspection.
For vans, note whether the noise changes when the vehicle is carrying a load. That detail may help the garage, but don’t assume that a knock is simply down to the weight on board.
A metallic rattle from underneath
An exhaust or another loose component may rattle against the underside of a vehicle. The AA also notes that a failing catalytic converter can sound like a loose exhaust. The location of a rattle can be deceptive from the driver’s seat, so ask a garage to trace it.
A rumble that grows with road speed
A wheel bearing problem may sound more like a hum or rumble than a bump. Tyres and other wheel related faults can make unfamiliar noises too. If the sound changes with speed, tell the garage. That pattern is more useful than trying to name the faulty part yourself.
A noise when braking or turning
A scrape, click or grind during braking needs attention. It might be a worn brake component or something caught near a brake disc. (It could also rust be rusty brake discs if the car’s been standing for a while). A knock while turning could involve steering or suspension parts. These systems affect how the vehicle stops and handles, so arrange a check promptly.
What about motorbikes?
Motorbike noises need the same care, particularly because a small change can be easy to feel as well as hear. Note whether the sound occurs over bumps, while braking or as you apply power. The chain and sprockets, suspension, wheel bearings and exhaust are all parts a mechanic may need to inspect. An excessively loose or worn chain or sprocket is treated as a serious MOT defect.
Before booking a check, make a short note of when the noise happens, where it seems to come from and whether it’s getting worse. If steering, braking or handling has changed, or the noise is severe, stop somewhere safe and seek professional advice before continuing. A description can help find the fault. Only an inspection can establish what it is and whether the vehicle is safe to use.
Generally speaking though remember, noises are warnings. You need to keep your vehicle safe and roadworthy, for your peace of mind and for your insurance. So, don’t delay, if you hear a bump that shouldn’t, be there, have it checked soon.
