can i use autodesk mudbox to make mesh for sims 3 obj? I plan to make simple objects for my sims 3. was wondering if mudbox is ok to make new mesh

I think you should ask create type questions rather from the create forums http://www.modthesims.info/forumdisplay.php?f=597
But sure you can create meshes or edit one in mudbox as long as you'll convert it to obj and import it to Milkshape (or Blender I suppose). But those meshes should be something like accessories etc. Not really clothes.