# LiftMaster 041B3869-3A Belt Drive Trolley Kit

The **LiftMaster 041B3869-3A Belt Drive Trolley Kit** is a genuine replacement trolley assembly designed for use with select LiftMaster and Chamberlain belt drive garage door openers. The trolley connects the opener carriage to the garage door arm, allowing the motor to open and close the door smoothly along the rail.

This replacement kit is used when the original trolley becomes worn, damaged, or fails to properly engage the belt drive system. Installing a new trolley helps restore proper door movement and reliable opener operation.

Always verify your garage door opener model and replacement parts diagram before ordering to ensure compatibility.

### Key Features

-   Genuine LiftMaster replacement part
-   Replacement trolley for belt drive garage door openers
-   Connects the garage door arm to the opener rail carriage
-   Restores smooth door operation when the original trolley is worn or damaged
-   Designed for select LiftMaster and Chamberlain belt drive opener systems

### Part Details

-   **Part Number:** 041B3869-3A
-   **Also Known As:** 41B3869, 41B3869-1, 41B3869-3
-   **Manufacturer:** LiftMaster
-   **Application:** Belt drive garage door opener trolley assembly

### Compatible Garage Door Opener Models

Compatible with LiftMaster garage door opener models including: 8155WMC, 8355, 8355-267, 8355W, 84501MC, 84504RMC, 8550WLB, and 87504R-267MC.

### Installation Notes

Disconnect power to the garage door opener before performing service or replacing internal components. Refer to the opener installation manual or replacement parts diagram to confirm correct part compatibility prior to installation.

## Details

- **Price:** 49.99 USD
- **Vendor:** Liftmaster

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 49.99 USD | In stock |

## Images

- LiftMaster 041B3869-3A belt drive trolley kit for garage door opener rail system
- LiftMaster belt drive opener trolley replacement part 041B3869-3A installed on rail
- LiftMaster belt drive opener trolley replacement part 041B3869-3A installed on rail
- Replacement trolley assembly for LiftMaster and Chamberlain belt drive garage door openers
- Garage door opener trolley connecting door arm to belt drive carriage system
- LiftMaster 041B3869-3A trolley kit for worn or damaged belt drive opener systems

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> Source: [Express Garage Doors](https://www.expressgaragedoors.com/products/liftmaster-041b3869-3a-belt-drive-trolley-kit)
> Updated: 2026-04-13