Ford Ka clunking steering - WD40 temporary cures

Erm, just a quick point, WD40 is very good at de-greasing whatever its sprayed upon. It probably isn't a good idea being too liberal with it around that area.

That aside...

When you say "clunking on full lock", do you mean a single clunk as you traverse to full lock?, or when at full lock, you hear/feel clunking repetitively as the car is driven? Does it happen less if the car is driven at some speed (not too fast, of course) - i.e. if there's less lateral force on the road wheels?

My complete guess, if single clunk would be a worn track rod end (reason

- same thing happened a short while ago to my Omega and was fixed by a local indy for ~£45 inc. tracking [now to find someone to do a full geometry :( ])

...or... lower suspension arm / bush (reason - the Wife's Ka suffered the same when she first bought it - repaired under warranty so no clue as to how much it cost back then - but I'd expect to pay £50-£80 for an indy to repair).

Why not phone a few local indy's?, they should agree to look at the problem to diagnose and then quote - remember, although this could be DIY'd you'd still need someone to look at the tracking later.

Some cars always make noises on full lock - it's an inherant part of the power steering so it *may* not be much to worry about but it does sound more than that.

Basic tracking can be DIY'd too with nothing more than a tape measure and a couple of spanners.