LiftMaster 8550 & 8550W Belt Drive Parts
LiftMaster 8550 and 8550W Replacement Parts
The 8550 and 8550W are DC belt drive openers with battery backup. The 8550W is the Wi-Fi version. Mechanically they are the same opener — same belts, rail, trolley, motor and hardware — and only three electrical parts differ: the logic board, the transformer and the cover. Those are marked in the Fits column below. Everything for both models is on this page.
The three parts that differ between the two models:
| Part | 8550 | 8550W |
|---|---|---|
| Logic board | 045DCT | 050DCTWF |
| Transformer | 041A7635 | 041D0277-1 |
| Cover | 041A7619 | 041D8257 |
Everything else on this page fits both. If you are unsure which model you have, the number is on the label under the light lens.
Beeping, running slowly, or dead during a power cut? That is almost always just the backup battery — it is a consumable and lasts a few years. See section 4. If the door reverses at the wrong point or will not learn its travel, that is the motor and travel module at key 07.
1. Motor Unit
First part of number below corresponds to key number above:
| Key | Part # | Description | Fits |
|---|---|---|---|
| 02 | 41D217 | End panel with labels, battery cover and light socket | Both |
| 03 | 041A7562 | Light lens | Both |
| 04 | 041C0279 | Light socket | Both |
| 05 | 041A7635 | Transformer | 8550 |
| 05 | 041D0277-1 | Transformer | 8550W |
| 06 | 041A7619 | Cover | 8550 |
| 06 | 041D8257 | Cover | 8550W |
| 07 | 041-0236-000 | Motor and travel module, DC | Both |
| 08 | 041D8071-4 | Travel module | Both |
| 10 | 045DCT | Receiver logic board | 8550 |
| 10 | 050DCTWF | Receiver logic board, Wi-Fi — now 050DCTBFMC | 8550W |
| 12 | 041B7611 | Filter board | Both |
| — | 041B7418 | Wire harness with screws | Both |
| — | LMLED1 | Universal replacement LED bulb, vibration rated | Both |
End panels and covers
Several versions exist. Compare against the part you are removing before ordering, or call and we will identify it with you.
| Key | Part # | Description |
|---|---|---|
| — | 41D216 | End panel with all labels and light socket |
| — | 041D0216-2 | End panel, without logic board |
| — | 041A7757 | End panel |
| — | 041D8175 | Cover |
| — | 041D8179 | Cover |
| — | 041D8181 | Cover |
Replacing the logic board? Read the number printed on the board you are removing and match it to the Fits column at key 10. An 8550W will not pair on a standard 045DCT board. If the number on yours is neither of the two listed, call (866) 965-5599 with it before ordering. The key 11 line cord (41B135) and the key 01 sprocket and cover (041C0589-2) are both discontinued.
2. Belt and Rail
The belt and the one piece rail are both sized to your door height. Measure the door opening, not the rail.
| Key | Part # | Description | Fits |
|---|---|---|---|
| R-01 | 41A5434-11 | Belt | 7 ft door |
| R-01 | 41A5434-13 | Belt | 8 ft door |
| R-01 | 41A5434-14 | Belt | 10 ft door |
| R-02 | 041B5424 | Belt pulley bracket | Both |
| R-03 | 004A1008 | Master link kit | Both |
| R-04 | 2777BD | One piece rail | 7 ft door |
| R-04 | 2778BD | One piece rail | 8 ft door |
| R-04 | 2770BD | One piece rail | 10 ft door |
| R-05 | 041B3869-3A | Trolley assembly | Both |
| R-06 | 041B4103 | Tensioner assembly | Both |
A belt rarely fails on its own — check the pulley bracket, trolley and tensioner while the rail is apart. A seized pulley or worn trolley will chew through a new belt in a matter of months. Lower cost aftermarket belts are available: 7 ft, 8 ft, 10 ft.
3. Safety Sensors and Brackets
| Key | Part # | Description |
|---|---|---|
| i-07 | 041-0136 | Safety sensor eye kit — sending and receiving eyes, matched pair |
| — | 041-0365-000 | Sensor eyes and brackets, 1997 to current — the complete set |
| — | 041-0155-000 | Safety sensor brackets, 2021 to present |
| — | 041A5281-1 | Sensor extension brackets |
| 09 | 041B4494-1 | Sensor wire, white and red/white |
| — | 041B0873 | Sunblocker bracket — stops sunlight false-tripping the eye |
If you need eyes and brackets, the 041-0365-000 is the complete set. If your brackets are sound, the 041-0136 eye kit alone is all you need. The i-06 sensor bracket (041A5266-1) is no longer available — the 041-0155-000 replaces it, and the older 41A5034 kit is replaced by the 041-0136.
4. Battery Backup
| Key | Part # | Description |
|---|---|---|
| — | G485LM | LiftMaster 12V replacement battery |
| — | Yuasa NP4-12 | 12V 4.5Ah sealed lead acid battery |
The battery is a consumable, not a fault — expect to replace it every few years. The opener runs normally on mains with a dead battery, it just will not work during an outage. The battery sits behind the cover on the end panel at key 02.
5. Door Hardware and Installation Parts
First part of number below corresponds to key number above:
| Key | Part # | Description |
|---|---|---|
| i-01 | 041B0035B | Curved door arm |
| i-02 | 041A5047-1 | Door bracket with clevis pin and fastener |
| i-03 | 041A2828 | Emergency release rope and handle |
| i-04 | 041A5047-2 | Header bracket with clevis pin and fastener |
| — | 041A4353-1 | Header bracket, black — belt drive units |
| i-05 | K029B0137 | Remote control visor clip |
| i-08 | 4178B0034B | Straight door arm |
| i-10 | 10A19 | 3V 2016 lithium battery — remote |
| — | 10A20 | 3V 2032 lithium battery — remote |
6. Remotes and Wall Controls
| Key | Part # | Description |
|---|---|---|
| — | 893MAX | 3 button visor remote — universal replacement |
| — | 889LM | MyQ control panel |
| — | 041A4202-6B | Wall control panel, two wire |
| — | 041A3504 | Antenna extender kit |
| — | L6950 | Multi purpose spray lube, green |
The 893MAX covers 371LM, 971LM, 973LM and 893LM, and is the listed substitute for 81LM, 83LM, 63LM, 753CB, 850CB, 853CB, 953CB, 953EV and Craftsman 53680, 53859 and 53879. The 98LM, 398LM and 888LM control panels are discontinued — the 889LM replaces them. The 841LM lock upgrade kit is also no longer available. Browse all LiftMaster remote controls.
More LiftMaster Parts
Belt drive rail and belt parts · All LiftMaster opener parts · LiftMaster remote controls