i just had the right side done in december now i hear the damn moaning again. i can only assume its the rleft side now. anybody know what causes the bearing to go bad? just regular wear and tear?

Do your aftermarket wheels have hubcentric rings? Aftermarket wheels can cause wear on the bearing over time if they are not centered correctly.

Also.. If the drive shafts are not torqued to proper specs then you can destroy the wheel bearing and/or the tranny bearing in a few 1000 miles.