how to replace back wheel bearings on volkswagon polo?

No need for that,have to remove rear hub,never done a polo but if it is discs you will have to remove caliper and disc if it is a drum brake remove drum and centre hub nut,maybe have to take hub to garage for a press out with the bearing maybe get a hub from a scrappy then it is just a direct replacement,hope this helps,ignore the previous a/hole

wickham
April 2010