wheel bearing?

you do not say how old your car is, would suggest you get a haynes manual which gives you full details. you will need access to a press to get old bearing out and to press new bearing in, when you have hub assembly off, go to a local garage, and ask them if they will do it for you, (about £10-£15). i have seen then taken out and put in with a hammer, but not a recommended way of doing it.

hope it helps
August 2010