A screech on every open usually comes from dry or worn rollers and hinges, not the opener. If the rollers still spin, a light lube often quiets it. Cracked or rattling rollers need replacing.
People blame the opener first. A lot of the time the racket is lower down, where the door runs on small wheels called rollers. Sort the forks before you buy a new head or drown the tracks in grease.
Each section hangs on rollers that ride inside the steel tracks on both sides. Plastic rollers get brittle. Metal rollers lose their bearings. Either way they stop spinning clean and start dragging. Dirt packs in. Old grease turns into grit. One stuck roller makes the whole door chatter.
If the rollers still spin and the hinges look fine
That is the lube path. Stand off to the side next time it moves. Watch a roller near the bottom. If it turns, even slowly, and the plastic cage is intact, a light garage door lubricant on the roller stems and the hinges often quiets the squeal. Wipe the excess. Do not soak the tracks like a fryer. Grease packed into the rails just holds grit.
Hinges that squeak without a flat roller can take the same light film at the hinge pin. Move the door a few inches by hand with the opener disconnected first. If the squeal drops after one careful pass, you found dry hardware, not a broken opener.
If the plastic cages are cracked or the bearings rattle
Spray will not save them. Spin a roller by hand with the door disconnected and standing clear. A cracked cage, a flat spot on the tire, or bearings that grind when you turn the wheel means replace, not lube. Shops usually swap rollers as a set on that side, sometimes both sides, so the door tracks even.
Plastic rollers get brittle after years of sun and cold. Metal rollers still squeal when grit gets inside. Cracked or flat hardware is a parts job, not a can of spray.
If the door binds, lists, or a cable looks wrong
A bent track or a loose hinge can screech the same way. So can a cable that has jumped a groove on the drum. Pull the emergency release and try the door by hand, slow, from the side. If it fights you on one corner, jumps, or tries to twist, stop. Stay out from under it.
A roller that has walked halfway out of the track is worse than a dry squeal. The door starts to lean. Do not shove it back in with a screwdriver while the door is hanging. A cable that looks frayed or jumped a drum can scrape and screech while the panels still look nested. Same rule: stop the opener.
What it is not
This is different from an opener that grinds like gravel. That grind lives up in the motor head. Roller screech lives down low, where the little wheels ride the steel. People oil the tracks for a head grind and miss the chewed nylon gear. People replace a gear for a roller screech and still have a squealing door.
It is also different from a door that already jammed with a roller hanging outside the rail. Screech for weeks is often the warning. Off track is the failure. If a wheel is already sitting in open air, you are past the lube and replace forks on this page.
What not to do
Do not keep mashing the button hoping the noise will seat itself. Do not hammer a roller home while the motor still has power. Do not stand under a hanging or listing door. Each wasted cycle can turn a dry squeal into a bent track or a panel off the rollers.
I am not a contractor. This is just what shows up when a door sounds worse every month and still mostly opens. A shop that does doors all day will pull bad rollers, check the track alignment, and see whether the opener is straining from drag or worn itself.
For a wider look at squeals, bangs, and grind noises, see fix a noisy garage door.
Manufacturer trade notes on residential door hardware live in DASMA's publications library. Those sheets are written for dealers and installers.
The U.S. CPSC garage door operator page covers federal entrapment rules for automatic openers. Keep kids and pets clear while you sort the forks.
If the screech is new and you want someone local to look, get a quote.