Do not lube the slides in the front channel! The leading edge of the glass has a thin plastic cover with a felt like finish attached to the glass. You can replace them but they are not supposed to be lubed. What kind of weather strips/ cat whiskers do you have between the top of the door and the side of the door glass. If they are the rubber ones, they really make it hard to roll the windows up and down. If you have the rubber ones, you want to replace them with the ones that are more like the original "cat whiskers" configuration.