At my siblings for Christmas the garage door was causing me great anxiety. Everytime it was opened or retracted, the motor would shake back and forth. the previous owners were a bunch of cunnermans that held the motor with hvac angle iron.
Step 1: tighten all the bolts. still shakes
Step 2: add a diagonal brace to the super chinsey hangers. Would open fine, but shake like a MF when closing.
Step 3: grease tracks/wheels, bearings, still shake
Step 4: see how crooked the motor is mounted relative the center track bar (blue oval). The red lines are the original position. So I remove the bottom bolt of the newly installed brace, Use my highly calibrated shoulder, I shove the motor over @4", and rebolt