Hi subaru community I could not find a DIY on rear bearings with many pictures so I had an opportunity to replace mine on a 03 wrx but the same should apply from 02-07 wrx sti. You will need some way of pressing these things out I used a 12ton hydraulic press. Parts that you need are below. I purchased off Rockauto 2003 SUBARU IMPREZA 2.0L H4 Turbocharged BECK/ARNLEY 0523678 (052-3678) Wheel Seal BECK/ARNLEY 0523677 (052-3677) Wheel Seal BECK/ARNLEY 0523700 (052-3700) Wheel Seal DURA INTERNATIONAL 29513248 (295-13248) Wheel Bearing Tools that will help: Hydraulic Press Bearing separator O ring remover Socket and old wheel bearing cases or you can use different size pipes Begin by removing the seals on the side facing the axle. Next you will press the hub out. When you remove the hub the Race will stay with it you will need a bearing separator to remove it Next Remove to retaining clip to press the bearing out, usually you use C clip pliers but mine broke so I used two flat head screw drivers. Now you press the bearing out from the outside. Clean inspect the bore on the spindle where the bearings goes in. whip it down with a clean towel. Then press it in until it bottoms out. Used the old bearing casing it works perfect to press the new bearing on the outsides of the race. Now place the retaining clip back in if the retaining clip does not snap into groove you did not press bearing all the way down and put the front seal on (again I used the old bearing casing to evenly put int on. Next you press the hub back in. you have to support the back of the bearing inner race otherwise it will come out if you don't. Now just put the seals on the inner side of the bearing there are two. Your done. The hub should spin smooth but it will have slight stiffness until you wear the bearings in.