Originally Posted by SteveH
Don't know, but my guess is you have it right with the friction anti-sway bar. I've had them bind and act like that before especially after they've gotten wet.
Yeah, we had the very same thing happen just a few weeks ago. We were driving on a road that was straight, hit some rain, then made a left turn on to another straight road. When we made our first right turn, bang. My guess is it rusted a bit and then let loose when it was overpowered by the turn.
I have a new theory that this is why they tell us to loosen them in the rain. It has nothing to do with "they'll keep the rig from straightening out, too" as some have proposed - it has to do with the fact that they rust and bind.