wow dont just go and replace it! rip the pig off and look at the drive shaft. check the bolt going to the pinion shaft. sometimes they come loose and you only need to tighten it.
how would i tighten the nut these guys are talking about at this link? http://www.vmoa.net/xoops/modules/newbb/viewtopic.php?topic_id=207&forum=2
and also my main question is do i pull the pig from the shaft housing? or just open the back side of the pig facing the rim? to get to this nut...