Hi, friend:
This 406 model has -segly- bi-masa clutch, which apart from generating the same problems as the common and others, is much more expensive.
Well, the most common failures in these bi-masa are:
1) squeak (crickets, according to a Spanish friend) when the modera car that pre-adunits a not very imminent break but is going to break and there, you must change the complete set: Bi-masa steering wheel plus the album itself and its thrust bearing (around here called "crapodine") cost of the piece in Argentina, about US $ 1000.-
2) Clutch skating: It comes as spare only the disc and the thrust bearing Luk brand and costs about US $ 350 in Argentina.
If you don't have those crickets, just change the disc and crapodine and walk well. I have done it in my 406 hdi. The workforce of the workshop, which is quite simple and can do it anyone moderately cunning, must not exceed what would be charged for changing a common clutch, since taking and placing is exactly the same in Ambois cases and does not even require special tools.
Luck.
I need the electrical schemes of the Peugeot 407 HDI Tiptronic 2.0 of 2005. There helps me?
Hugs and here I am.
Ruben from Argentina