The relevance of a Dual Mass Flywheel.
There has been a lot of controversy of late, especially as seen over the internet as to why vehicle manufacturers are opting to supply dual mass flywheels over their single mass counterparts when the DMF is known to be unreliable and very expensive. As an owner of an X-Trail I can assure you that the replacement is not cheap – from the supposed sound of a worn release bearing to a full clutch replacement is going to cost you upwards of 2 000 U$ so be prepared. This clutch by the way had done 144 000 Km and still worked fine. It’s an eight hour job so don’t take it lightly.
An interesting video showing the DMF is shown below.
Fitting the Dual Mass Flywheel
Many fitters claim to be able to skim the flywheel but this is not advisable as the spring around the inner part of the flywheel will in all likelihood be worn. The flywheel will make a noise over time and you may not even be aware of it – once the flywheel has been replaced this will be immediately noticeable, less noise especially doing acceleration. The manufacturer will not advise a user to replace the clutch with a single mass flywheel kit. One of the advantages of the DMF is gear changing and you’ll find many drivers complaining of the conversion kit causing an entire change to their driving habits. I would not know – most of the cars I have driven all had SMF but had no problems in either gear changes or four cylinder vibration. I’d be interested to hear of anyone having done the conversion and whether it was worth it, especially to large capacity 4-cylinder engines.