What does the DMF do in our Citroen C4 Picasso and does it need replacing with the clutch?

The clutch in my partner's C4 Picasso is screaming like a Banshee when depressed. My local independent garage guy tells me the clutch needs replacing and it would be foolish not to change the dual mass flywheel at the same time. The cost is horrendous, considering the last clutch I had replaced was on my 1982 Escort Ghia about 18 years ago. What does the DMF do and should it be changed at the same time please?

Asked on 26 October 2013 by MP, via email

Answered by Honest John
The DMF protects the transmission from torque reactions. Without it, first and second gear would not last very long. Your 1982 Escort had about 70Nm torque, but 300+Nm torque is now very common, even from a 1.6 diesel. That said, Ford has managed to achieve the same effect of a DMF by reprogramming the engine management of its 1.6-litre diesels.
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