If it's moving slowly, liberally spray some Silicone Spray Lube down both rubber channels, then run the window up and down a few times. That stuff goes on like water, evaporates, and leaves a film of "slippery" behind. Works great on sluggish seat belts too that don't like to retract on their own.
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Tuesday, September 25th, 2012 AT 4:13 AM