Gearbox(?) rattle at low rpm.

[Alex of Smeg]

Have a 2011 type S tourer. There's an odd rattling noise when pulling from low revs. Most noticeable when engaging the clutch. For example I can hold the brake and bring the clutch to the bite point and I hear it. Reminds me of a noise from a loose heat shield on an old car. The fact that it does it in all forward gears but not reverse makes me think it could be a gearbox problem. Anyone any ideas? 

[Trevor]

It does sound very much like the Dual Mass Flywheel (DMF) is breaking up.

If this is the case then you will hear a series of loud 'clunking noises' when switching the engine off and then eventually it will lose drive completely.

It may also be the clutch mechanism (self adjusting ramps) if completely worn out, and all of this could be inherited from a previous owners driving style.

[Alex of Smeg]

2 hours ago, Trevor said:

It does sound very much like the Dual Mass Flywheel (DMF) is breaking up.

If this is the case then you will hear a series of loud 'clunking noises' when switching the engine off and then eventually it will lose drive completely.

It may also be the clutch mechanism (self adjusting ramps) if completely worn out, and all of this could be inherited from a previous owners driving style.

  

Just seen the price of these DMFs 😬 would the fact that it doesn't happen in reverse agree with this? It is 180'000 mile car. 

Self adjusting ramps? not familiar with these. Either way it sounds like I'm gonna have to take the box off and may as well replace the lot. Maybe a job for when the weather improves. Hope it doesn't catastrophically fail before then!

[Trevor]

Not sure why it wouldn't make a noise in reverse if it were a DMF issue though.

The clutch works on a self adjusting 'sliding ramp' system which wears over time and will allow the clutch to slip, not sure if it is the clutch mechanism that is worn but as you say, the only way would be to remove the transmission and see what is going on in there.

However, one other thing has occurred to me and that is if it is not on the gearbox side but in fact the front of the engine, e.g. the air conditioning compressor pulley which are prone to breaking up and making a rattling noise or even the crankshaft pulley which can also go the same way.....easy way to check this is to temporarily remove the auxiliary drivebelt and run the engine to see if the noise has disappeared