BrownST

I didn't even think about having the wheelbase measured at the time but yes that would have proven the point. From memory the only outliar on the alignment sheet was the tracking but who knows if the other readings were'tweaked' as I got frustrated with it and went at it with the tools before getting my own alignments results. I should say that the actual reason I'd undone the wishbone in truth is because I initially suspected the loading of the impact had damaged the wheel bearing so what I actually did was remove the arm and the hub at the same time so I could inspect everything. Although the bearing did seem smooth and free and rotated without any sticking points in it's operation I still replaced it as I'd bought one so it may have well been the problem but I felt like the two bearings felt the same by hand but under operating conditions I guess there very well could have been a difference. Still, all is well now.

I know this is a year late and you may possibly not have the car anymore but I thought I'd post my experience here for anybody in the future that may have this problem and it took me a while to put my finger on it. I have a MY14 Fiesta ST which drove fine from new then on my way to work one day a van collided with the LHS on a roundabout and I caught the RF wheel on the kerb on the roundabout. So the car was repaired and all sorted and I asked for an alignment check and all came back fine, the garage adjusted the toe slightly to bring it back in line and called it done. I drove it for a while and I was convinced something was wrong but on paper all was fine. It would drive as the OP described, it would turn in one direction as it should but it just didn't feel right in the other direction. After being frustrated with it for a while I loosened both lower arm mounting bolts and tightened them back up and this solved the problem. I suspect that the impact was enough to move the lower arm on it's rear mounting as it's slotted affecting the suspension movement in ways I cannot explain haha