LiftMaster 41C4677 Screw Drive Trolley Assembly

The LiftMaster 41C4677 Screw Drive Trolley Assembly is an OEM replacement carriage designed for select LiftMaster and Chamberlain screw drive garage door openers. This assembly travels along the screw-drive rail to engage and move the door, and it integrates the manual emergency release so you can disconnect the door from the opener when needed. Replacing a worn or broken trolley restores smooth door travel, resolves issues like slipping or failing to engage, and helps maintain reliable operation in residential applications.

This replacement part is intended only for screw drive systems and is not compatible with chain or belt drive rails. For correct fit, match the 41C4677 part number to your opener’s parts list or the label on the existing trolley/rail in your owner’s manual. Installation typically involves disconnecting power, releasing the existing trolley, sliding the new trolley onto the screw-drive rail per the manufacturer’s procedure, reconnecting the release cord, and reprogramming or fine-tuning travel and force settings as directed in the opener manual. Always test safety reversal after installation. Using the genuine LiftMaster 41C4677 trolley assembly ensures proper engagement with compatible LiftMaster/Chamberlain screw-drive openers and maintains designed performance and safety.