If you get resistance every time you go in and out of your sliding door it is probably due to dirt and grime build up. Make you exit and entrances easier by first vacuuming the track of the door. Now, apply furniture polish to a cloth and rub into the track, every crevice. This will not only lubricate the door, but will prevent the dust and dirt from settling back into the grooves of the track. Easy in and easy out!