WD-40 twice a year should do it. While you are at it you should lubricate the bearings in the rollers and all hinges on the door. I like silicone spray but you can also use 30 weight motor oil.

Thank you for your reply.

If WD-40 does anything, no lubrication was needed.

All it leaves behind is some paraffin, and a very thin layer at that.

Most of what comes out of the can is solvent that evaporates.

Strange that the spring manufacturers recommend WD-40. Brickeye I'll put them in touch with you and just maybe you can straighten them out.

WD40 is a water displacer not a lubricant.

If they recommended it as a lubricant they are about as dumb as a post.