the front passenger side seatbelt locks up all the time. my wife ends up having to take it off and reset the belt multiple times during a trip. Does anyone have any suggestions on how to fix this?

 

Beat the GM engineers with a stick.

The problem is that the seat belt is too short, and if you extend it all the way it thinks it's in "child car seat" mode, so it locks in position.

We had to get a seat belt extender from the local dealer (free of charge, show up with your registration card so they can get the VIN number) but they'll probably have to order it.

Seat belt extenders are a crappy solution to the problem...but they're the ONLY solution I know of.