1998 Ford Explorer • 222,648 miles

When car shifts gears I hear a popping noise coming from underneath the truck around the center of truck. Could there be something wrong with the transfer case? Also, sometimes when I put it in park and go to leave again, it wants do anything because it's not all the way engaged in park so I have to put it in neutral to start it.
September 25, 2013.

Check u joints and center bearing if you have one first. Then have a pro look at tcase if the joints are ok. If you see rust around joints replace them.

Sep 26, 2013.