DIAGNOSIS A grinding on the 'up' cycle only usually points to worn gear in the opener's motor unit, specifically the plastic drive gear. The B2405 uses a plastic gear as a safety clutch; when it wears out, the metal motor gear grinds against it.
FIX You'll likely need to replace the main drive gear assembly. It's a common repair kit. 1) Unplug the opener and lock out the door. 2) Remove the light cover and then the main housing cover. 3) You'll see the motor and gear train. The plastic gear is behind the larger hub. The kit includes instructions for removing the old gear and installing the new one. The key is getting the new gear aligned properly on the shaft.
IF THAT DIDN'T WORK If the noise persists with a new gear, the issue might be in the door itself, not the opener. A binding door (like a bent track or seized roller) puts extra strain on the opener. Disconnect the door and run it by hand—it should move smoothly with little effort. If it's stiff, the problem is in the tracks, rollers, or springs, not the opener.
HEADS UP Don't keep running it with that grind. You'll quickly wear out the more expensive motor sprocket. The plastic gear is designed to be the sacrificial part.