Ed, that is the same window that I had a problem with the day that I delivered the car to the shipping company to take it to Texas. The glass had cracked when it came loose from the track, and Nick had a local glass company replace it. The glass is set in a special setting tape that you push the glass into it after you fold it into the track. Once it is set in the track, you spray it with an oil, such as WD-40, and the setting tape expands, holding the glass tightly in the channel. My guess is that the tape has dried out from the Texas heat, and it has lost its grip on the glass. Clean the glass and gently push it back into the channel. Spray it with oil, and the next day, clean the glass again. I wouldn't recommend using any other type of product, as it would make cleaning the channel difficult if the glass were to get damaged again. Do it correctly the first time. If you need new setting tape, your local glass supplier should be able to supply you with a strip at a minimal cost.