stanley garage door opener
Another thing to do is to make sure all bolts and screws in the door are snug. Mine work loose every other year and that prevents the door from working smoothly.
One more thing: The rollers can wear out and wobble on the stems, or even break free of the stems. Check them all. They're cheap and easy to replace, but do that one at a time with the door closed so it doesn't fall on you.