Anyone that has owned a fiesta or any ford for that matter, has probably changed the wishbones. Signs that your wishbone is knackered are usually when your car tracks all over the place and knocks when going over bumps. Generally wishbone bushes dont just give up the ghost for nothing, if your car is lowered then that will be putting extra stress on them or if theres powersteering fluid/oil leaking on them it can make them deteriorate very quickly, so check when your replacing them.

Heres what can happen.

Its worth noting that there is a few different configurations for the whisbones, ie, 2/3 bolt and whether the ball joint is angled (power steering or not).

This a pretty simple job, should take no more than a hour a side. Its advised to replace in pairs, if only one side is done it can cause uneven-ness in the suspension.

Start by jacking up and supporting the car, removing the wheel. Nows a good time to spray the bolts with WD40 or some other penetrating lube. Theres 2 holding the wishbone to the carrier and one securing the ball joint the the hub.

Next take out the pinch bolt securing the ball joint to the hub carrier. T45 Torx bit is required here and 17mm Socket. Also this bolt must not be re-used, it is a stretch bolt! Now its a case of getting the ball joint out. Usually a few hits with a hammer is enough, or use a prybar to force it out. If it wont budge at all, (last resort) heat it up and give it a good hit!

Undo the bolts holding the wishbone to the carrier, to get to the back nut you might find it easier to remove the arch liner as its hiding behind it, however you can get a spanner on top to hold it with removing it. Remove the wishbone.

If your find the anti roll bar seems to be getting in the way at any time, its probably because only one side is jacked up, when the car is jacked evenly both sides this will move the roll bar out of the way.

Refitting is reverse of removal. Make sure you do everything up tight and dont forget to replace the pinch bolt.

Now you can do the next side.