Are we talking 2G or 1G AWD? If it's a 1G, it can only pop out of the diff (because it's bolted to the companion hub on the wheel side). A 2G can come out of the diff or the hub assembly itself since it goes all the way through.
The only way it can pop out is if you have *a lot* of play in the rear suspension on that side. I would check everything (trailing arm, control arm, sway bar end link, etc.) for cracks or missing nuts/bolts. I can't imagine that anything back there could move enough to allow it to fall out without some real evident signs of a problem.
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Ross
1996 Talon AWD
Best ET: 12.254 (small 16G)
Best Trap: 114.35 mph
http://members.xoom.com/RossSL/http://sfla.dsm.org Webmaster
