ford focus wheel squeak after pot hole?

hi Humphrey,
My Focus (X Reg) squeaks as well when turning left and when going over irregularities in the road surface. The sound appears to be coming from the right front end. Though the garage can't find the problem - they think it may be the bottom ball joint ! Forcing grease into it reduced the squeak a little for a while but no lasting repair was acheived. If you find out what yours is you might let me know ! It is really aggrevating.

Alfax
April 2009