Squeaking where exactly?
Try using some oil in the window runners to start, spray generously and put window up and down to lube. We do this as part of our general service too since these windows like to squak and get dry. Be sure to put the nozzle tube into the runner and go up and down, the back and small portion before the side mirror. You may see some streaking along the window edge but thats cool, it will go away or you can clean it off, your choice.