Steering Judder on corner
 

Thanks for looking at this thread guys any advice you can give will be much help.
Ok so i have had this probelm about 6 months now and have not been able to identify the cause.
There is a quite a Judder through the car/steering wheel when i corner (only turning left) at a speed over about 30mph. On a slight corner it is not noticable only when cornering quite hard. It feels as though the front right wheel is slipping across the road when turning under load.
The car other that this drives fine, I can select gears easily and there is no knocking sounds when turning right or heading in a straight line at any speed.
I have thought of some things it could be and have ruled most out. I have replaced the Anti Roll bar on the front right (the wheel i think the probelm comes from) I have replaced the suspension to Apex coil-over also.
The drive shaft as far as i understand would cause a clicking sound when turning at any speed and in all directions. Other possible ideas i have had include a sticky caliper/warped hub/warped disc but all of these seem unlikey to cause this?
As i say any ideas/suggestions would be much appreciated.
Thanks again.