So when I bought my 307 a couple of years ago, the lower engine mount was one of the parts I replaced (to cure a judder when taking up drive).
Recently I noticed the judder was returning and on inspection was cracked, so I replaced the bush part of the mount.
![Image](https://scontent-lhr3-1.xx.fbcdn.net/hphotos-xap1/v/t1.0-9/12107053_540658029416784_8567119133299772292_n.jpg?oh=f5ac80ba0820fa491c167fe82c9877a5&oe=56A84410)
I fitted a polybush one made by Powerflex, unlike the original type it just pushed with fingers, no hydraulic press required!!
The car is now wonderfully smooth to drive, with no judder.
![Image](https://scontent-lhr3-1.xx.fbcdn.net/hphotos-xap1/v/t1.0-9/12107865_540658529416734_5803842387908289585_n.jpg?oh=2b05911d580e58f2c31b4ae7786f16e8&oe=568EAE17)
This may help someone, it was a 65mm bush I fitted to my 307, ironically the same size as on my Xantia years ago, and the Powerflex part number is PFF50-420 for a yellow bush.
Better add I don't work for either company.