Wouldn't that "sticky residue" also collect dust & dirt like the
grease?

On 8 Dec 2005 19:25:01 -0800, wrote:

No you should not use grease in the rails since grease will collect
dust & dirt and actually make it harder for the rollers to move thru
the track. The door rails don't need any lubrication, but the rollers
(if they have bearings), hinges, and pulleys should be oiled on a
regular basis w/ oil made for doors or even light weight motor oil.
WD40 evaporates rather quickly & leaves a sticky residue so using it
has no benefit at all.