LiftMaster 15-48B18LGE Drive Sprocket — #48, 18 Teeth, 1-Inch Bore

The LiftMaster 15-48B18LGE is a 18-tooth sprocket specified for #48 chain with a 1 inch bore. It belongs in the exact drive arrangement identified by the equipment documentation. Match the chain, shaft interface and drive ratio together rather than treating an approximately similar sprocket as an interchangeable replacement. Select the replacement by the complete part number and the installed equipment configuration. A similar photograph or a shared LiftMaster brand name does not establish interchangeability. Confirm the applicable service drawing before ordering so the repair addresses the correct component and its related mounting, connection and operating requirements.

Compatibility — Models, Versions and Exclusions

Identify the Assembly and Plan the Repair

Identify the sprocket position in the exploded drive drawing. The same operator can contain output, reduction and travel-limit sprockets with different functions. Record the existing part reference, shaft engagement and chain alignment before ordering. Do not use a replacement tooth count to change speed or compensate for a door that is difficult to move.

Confirm the 1 inch bore against the actual approved shaft arrangement and inspect the mating keyway, hub and retaining hardware. Have the technician assess chain wear and tooth damage together. A new sprocket cannot restore a damaged shaft or elongated chain, and excessive chain tension is not a repair for incorrect alignment or mismatched components.

Compare the replacement with the installed service arrangement before dismantling the equipment. Photograph the part’s location and record the complete model and visible service numbers. Inspect the surrounding attachment points and mating components for wear, impact damage or misalignment. Replacing one worn item will not correct a damaged support or another component that continues to impose abnormal loads on the repaired assembly.

Plan the repair around the manufacturer’s instructions for the actual equipment revision. Confirm access, safe support and any separate hardware before removing the old part. After installation, restore the intended retention, alignment and guarding, then test the equipment under controlled conditions. The repair is complete only when the original fault has been addressed and the system’s required operating and protection functions have been checked.

Specifications and Product Identification

Before Ordering

• Confirm the full chain and tooth specification.
• Verify bore, keyway, hub and retention.
• Identify the correct drive position and approved ratio.
• Inspect mating chain, shaft and guards.

Package Contents and Separate Requirements

This offer identifies the sprocket. Chain, master links, shaft, key, companion sprocket and complete drive assembly are separate unless expressly included in the current supplier package. Confirm any set screws or other retaining pieces before disassembly. Nearby components in the operator drawing describe the assembly and do not by themselves establish this carton’s contents.

Safety Warnings — Read Before Installation or Service

• WARNING: A moving commercial door and exposed drive sprocket — #48, 18 teeth, 1-inch bore can cause serious injury or death. Have a trained door-systems technician perform installation and service.
• Disconnect mains power and any battery backup before mechanical work or wiring. Secure the door against unexpected movement as directed by its manufacturer.
• Do not work on springs, cables or counterbalance components without appropriate training. Never bypass safety sensors or increase force to overcome binding.
• Restore guards and complete the model-specific travel, reversal and protection-device tests before returning the door to normal operation.

Related Products and Important Differences

• CPS-U monitored photo eyes — separate protection devices for approved commercial-door controls; match the operator and environment.
• TDC12X1BMC MAXUM trolley operator — a complete-operator comparison, not evidence that this legacy service part fits MAXUM.

Frequently Asked Questions

Does matching chain size prove compatibility?

No. Bore, hub geometry, retention and the approved drive relationship must also match.

Is it a complete shaft kit?

No. This listing identifies the sprocket service component.

Should the chain be inspected too?

Yes. Worn chain or a damaged shaft can undermine a sprocket-only repair.

Can I change tooth count to overcome a heavy door?

No. Correct the underlying mechanical problem and use the approved drive selection.

Need Help Confirming the Right Product?

Contact Garage-DoorParts.com before ordering. Send the full equipment model, readable part labels and photographs of the installed assembly. Include the dimensions, electrical configuration or accessory details relevant to your project so the listing can be checked against the actual installation.