Yes, an engine mount can fail an MOT in the UK if it is broken, excessively worn, insecure or allows dangerous engine movement. Severe vibration, knocking or engine movement under load can all become MOT concerns.
Engine mounts secure the engine and gearbox while reducing vibration. If a mount is broken, loose, detached, badly worn or allowing excessive engine movement, it can become an MOT failure.
Minor age-related wear may not fail by itself, but obvious insecurity, excessive movement, collapsed rubber or damaged brackets should be repaired before the test.
The engine is heavy and moves under load. The mounts stop that movement becoming excessive while absorbing vibration. When a mount fails, the engine can rock too far and pull on exhaust parts, hoses, wiring and driveshafts.
The issue is not just comfort. A badly worn mount can become a security and safety concern.
Cracked, separated or collapsed mount components can fail.
The engine or gearbox moves too much under load, especially when pulling away or changing gear.
Loose bolts, damaged brackets or failed mounting points are a concern.
Failed rubber can allow harsh contact and strong vibration through the body.
Excess movement can pull hoses, wiring, exhaust parts, intercooler pipes or driveshafts.
Badly split rubber or leaking hydraulic mounts may need replacement.
Mount symptoms can feel like clutch judder, gearbox faults, exhaust knocks, suspension knocks or misfire vibration. That is why the mount should be inspected instead of replacing parts by guesswork.
These checks help separate a normal vibration from a mount that may be unsafe or insecure.
A knock when setting off, changing gear or lifting off can point to mount movement.
Excessive vibration at idle may suggest a collapsed, torn or hardened mount.
Look for split rubber, loose brackets or leaking hydraulic mounts if visible.
Large rocking movement when load changes can indicate worn mounts.
Exhaust mounts, driveshafts, hoses and wiring can suffer if movement is excessive.
A garage can safely check engine mounts, brackets and gearbox supports.
Yes, if the mount is visibly damaged, the engine moves excessively or the car has strong vibration or clunking. Mount faults usually worsen over time and can affect comfort, drivability and nearby components.
Replacing worn mounts can make the car feel smoother and may prevent extra strain on exhaust parts, hoses, wiring and drivetrain components.
Some mounts are easy to access. Others are buried under pipes, battery trays, subframes or brackets. Hydraulic mounts and genuine manufacturer mounts can also cost more than simple rubber mounts.
Read repair costs guide →Many vehicles use several mounts, including engine mounts and gearbox or transmission mounts. A fault in any of them can cause similar symptoms.
If the car clunks when changing gear, judders when pulling away or moves harshly when you lift off the throttle, both engine and gearbox mounts should be checked.
Some vehicles use hydraulic mounts filled with fluid. When they leak or collapse, vibration can increase sharply. A leaking mount may not look dramatic at first, but if it has collapsed or allows too much movement, it needs attention.
A mildly worn mount may only cause vibration, but a broken or loose mount should not be ignored. Excessive movement can damage exhaust flexi pipes, coolant hoses, wiring, driveshafts or gear linkage parts.
On a test drive, pay attention to vibration at idle, clunks when pulling away and harsh movement when changing gear. These can be signs of worn engine or gearbox mounts.
Common questions UK drivers ask about worn mounts, vibration, gearbox mounts and MOT failure risk.
Yes, if the wear is severe enough to make the mount insecure or allow excessive movement.
Yes. Increased vibration at idle is one of the most common symptoms.
Yes. Gearbox or transmission mounts can also become worn, loose or damaged.
It can be. Severe movement can strain hoses, wiring, exhaust parts and drivetrain components.
Costs vary widely depending on the vehicle, mount type and access.
Have the mounts inspected if you notice clunks, vibration or visible engine movement.
Motor Vehicle Expert publishes practical UK-focused vehicle diagnostics, maintenance, MOT, used car and repair cost guidance based on common driver questions and real-world garage situations.
