for 2 years I lived with this and I figure I should take a look to see if I can do something. One of our OverHead garage door openers (10+ years old..???...maybe more) makes a thud...thud...thud noise as it opens / closes. I can not really tell where the noise is coming from. From outside, when the affected door starts to open, it looks like one side of the door sort of starts going up first...or one side it sticking...I think one side just starts before the other.

Any ideas what to adjust?