Window problems are probably one of the most common issues on the VX.
They are notorious for binding, sticking, jumping the track, tilting, burning up the motors due to the severe binding....you get the idea..
Here's a TON of threads that have good info on the issue and how to repair. These threads are all helpful, so I collected them and saved them in one place, just for instances like this. They are ALL important to read, so you'll understand all the issues with them.
As time went on, "most" found that buying the SBC metal brackets for $65 was the best fix. It's what I did.
I know there's a lot here to read, but it's been a very common issue and many have tried different things to solve it......
http://www.vehicross.info/forums/sho...window+binding
http://www.vehicross.info/forums/sho...ow+binding+fix
http://www.vehicross.info/forums/sho...n+track+window
http://www.vehicross.info/forums/sho...window+binding
http://www.vehicross.info/forums/sho...58&postcount=4
http://www.vehicross.info/forums/sho...ow+binding+fix
http://www.vehicross.info/forums/sho...threadid=10278
http://www.vehicross.info/forums/sho...7&postcount=26
http://www.vehicross.info/forums/sho...0&postcount=27
http://www.vehicross.info/forums/sho...7&postcount=31
http://www.vehicross.info/forums/sho...8&postcount=38
http://www.vehicross.info/forums/sho...+binding+track
http://www.vehicross.info/forums/sho...t=window+track
http://www.antiquecaterpillar.org/vx...cal/Window.asp
http://www.antiquecaterpillar.org/vx...indow_Bert.asp