For us, the first thing has to be truthfulness. The garage door opener is engineered so that it operates at the same speed throughout, at least here in the US where we have a stable power supply. ALL garage doors operate at 7 inches per second throughout their lifetimes. Slow doors are something clients do call about periodically, but the slowness is ALWAYS related to the door and not the opener. Sometimes the door is so heavy that it slows the opener down. There is no “pulley of the door” that wears out. 84″ (7 feet) divided by 7 inches per second means that a standard door will open in 12 seconds. Please stop talking about the pulley. You might mean drums, but we don’t lube those. Lube will NOT fix a slow door. Only adjusting the spring tension and/or tracks can do that.