Originally Posted by Styrak
You don't need to "grease your spring".
I'm surprised no one has mentioned that yet.
It's not required, but it can extend the life of the spring. It's used in industrial applications and has been for many years. When I see springs gooped with grease, I'll remove most of it, but leave a little bit on there.
Highny, you can use garage door grease available at Canadian Tire for gears, springs and spring guides (only if you have a metal spring guide though).