2007 Ford Explorer XLT 4X4 with TracControl (or whatever they call it),
about 4 months old.

Yesterday I went around a small traffic circle to make a left turn and I
heard a "clunk" sound in my transmission. I was only a half block from home,
so I didn't notice anything else.  Later, when I backed out of my driveway,
the transmission sounded a little strange and I noticed the 4X4 light was on
on my dashboard. I pushed the 4X4 High button on the dash to see if that
would turn the light off, it didn't go off. I pushed the 4X4 Low button and
the 4X4 Low light came on. Then I pushed the 4X4 Low button again, and the
light went off and the transmission was back to its regular mode. I tried to
see if it would happened again by "zipping" around the traffic circle again,
but nothing happened. Everything seems to be running normally since then.

My question: Is this a rare quirk? Could it switch to 4X4 when I'm on the
freeway? Can the Ford dealer run any tests to see if he/she can find
something?

Thanks for any responses.

Tom