The LiftMaster 16-4L290 Commercial V Belt, Medium Duty is an OEM replacement drive belt engineered for select LiftMaster commercial door operators. It delivers reliable power transmission from the motor pulley to the operator’s drive assembly, helping restore smooth, quiet operation and consistent door travel in warehouses, loading docks, service bays, and other commercial facilities. This belt is intended for maintenance and repair scenarios where a worn or slipping belt needs to be replaced to maintain performance and reduce vibration in belt-driven LiftMaster systems.
Identified by its 4L290 profile, this replacement part should be used only on operators and configurations that specifically call for it; always confirm compatibility in your LiftMaster model’s parts diagram or service manual. Installation is straightforward for qualified technicians: disconnect power and follow lockout/tagout procedures, verify pulley alignment, fit the belt over the pulleys, and set belt tension to the manufacturer’s specification, then recheck tension after initial run-in. Regular inspection for glazing or cracking and timely replacement support dependable, medium-duty operation. No programming or electrical adjustments are required for this mechanical part. Common search terms include LiftMaster commercial door operator belt, 4L290 V-belt, OEM replacement, medium-duty garage door opener belt, and commercial overhead door operator belt.