Failed wheel bearings do happen but unless you or a previous owner was forging rivers I don't think it's too likely. Do you have excessive side play in your front wheels? Have your hubs been slinging excessive grease? If not then I would remove & inspect before purchasing new. Once removed bad wheel bearings are easy to spot. Things to look for are: damage to the cage, discoloration to the rollers (should be shiny silver), pitts or grooves worn in rollers, contamination with foreign material, grooves or wear in outer races. If all this looks okay then I'd simply repack & reinstall. With all the Chinese junk out there these days I would suspect an original set of bearings in decent shape are better than a new set of "economy" wheel bearings. If you do need to replace them, if you can't afford Toyota I would go with Timken or National. For grease seals I use BECK/ARNLEY Part # 0523500. I usually get those from www.rockauto.com for about $3 each. Tim