Chamberlain Belt Drive Belts & Rail Parts

Which Chamberlain Belt Do I Need?

Nearly every Chamberlain belt drive opener built since the Whisper Drive generation uses the same belt, the 41A5250. Only the length changes, and the length is set by your door height, not your rail. Measure the door opening, pick the matching belt, done.

Door Height Belt Length Factory (OEM) Aftermarket
7 ft 41A5250 234" approx Factory belt Aftermarket belt
8 ft 41A5250-1 258" approx Factory belt Aftermarket belt
10 ft 41A5250-2 307.5" approx Factory belt Aftermarket belt
Not sure which one you need? Two checks:
  1. Measure the door opening height — 7 ft, 8 ft or 10 ft. Measure the door itself, not the rail. Most homes are 7 ft.
  2. Count the ribs on the old belt. Lay a tape along the belt and count the grooves inside a 6" span. 20 grooves is the 41A5250. 12 grooves means you have an older 41A3589 belt, covered further down.

Your model number is on the label under the light lens on the motor unit. Still not sure? Call (866) 965-5599 or email parts@gatehousesupplies.com with the length and rib count and we will confirm the part before you order.

Factory Belt or Aftermarket Belt — Your Choice

We stock both versions of every belt. The factory belt is the genuine Chamberlain part in original packaging, the same belt the opener shipped with. The aftermarket belt is built to the same length, the same rib pitch and the same end fittings by an independent manufacturer, and it typically costs about a third of the factory price. It installs identically and runs the same.

For a homeowner making a one-time repair, the aftermarket belt is the sensible buy. Choose the factory belt if you need the genuine part number on an invoice or you are supporting a warranty claim.

Chamberlain Models That Use the 41A5250 Belt

Numbered and legacy models

  • 8100
  • 8100M
  • 8200
  • 47995D
  • 248739
  • 248754
  • 349544
  • 349544EV

B series

  • B353
  • B373
  • B500
  • B503
  • B510
  • B550
  • B552
  • B730
  • B740
  • B750
  • B970
  • B980
  • B1381
  • B2202
  • B2210T
  • B2211T
  • B2212T
  • B2215T
  • B2401
  • B2405
  • B4505T
  • B4603T
  • B4613T
  • B4643T
  • B6713T
  • B6753T
  • B6753ST
  • B6755T
  • B6765

HD series

  • HD420EV
  • HD520EV
  • HD520EVG
  • HD600
  • HD750WF
  • HD750WFC
  • HD800
  • HD800D
  • HD900D
  • HD920EV
  • HD930EV
  • HD950WF
  • HD950WFC

LW series and MyQ

  • L9000WFC
  • LW500EV
  • LW600WFC
  • LW2000
  • LW3500
  • LW3500EV
  • LW5000EV
  • LW6000WF
  • LW9000WF
  • MYQ-CFGDO1

WD Whisper Drive series

  • WD822K
  • WD822KD
  • WD822KS
  • WD832KD
  • WD832KEV
  • WD832KEVC
  • WD850KEVG
  • WD900D
  • WD912K
  • WD912KS
  • WD922K
  • WD952KD
  • WD952KLD
  • WD952LD
  • WD962KD
  • WD962KEV
  • WD962KEVC
  • WD962KLD
  • WD962KPEV
  • WD962MLEV
  • WD962MLEVC
  • WD1000WF
  • WD1000WFC

Older Chamberlain Openers

Two earlier belt generations are still supported, and both are stocked here. If your belt has 12 ribs in a 6" span rather than 20, you have the older 41A3589 belt.

Belt Door Ribs Chamberlain Models Factory Aftermarket
41A3589-3 7 ft 12 9200, 9500 Factory Aftermarket
41A3589-1 8 ft 12 9200, 9500 Factory Aftermarket
41A3589-2 10 ft 12 9200, 9500 Factory Aftermarket
41A5434-11 7 ft 20 T-rail units Factory Aftermarket
41A5434-13 8 ft 20 T-rail units Factory Aftermarket
41A5434-14 10 ft 20 T-rail units Factory Aftermarket

Have a LiftMaster Opener?

LiftMaster belt drives use the 41A5434 and 41A3589 belts rather than the 41A5250. See the model chart on our LiftMaster belt drive rail parts page, or browse all LiftMaster opener parts.

Belt Drive Rail Parts Diagram

A belt rarely fails on its own. With the rail apart, check the idler pulley, the trolley and the belt tensioner — a seized pulley or a worn trolley will chew through a new belt in a matter of months, and all three are inexpensive next to a second belt. Use the diagram to identify your part, then click the part number in the table below.

Chamberlain belt drive rail assembly parts diagram

First part of number below corresponds to diagram number above:

Ref Part # Description
01 004A1008 Master link kit
03 183B112 Rail braces
06 41A5250 Belt assembly, 7 ft door — standard Chamberlain belt
06 41A5250-1 Belt assembly, 8 ft door — standard Chamberlain belt
06 41A5250-2 Belt assembly, 10 ft door — standard Chamberlain belt
06 41A3589-3 Belt assembly, 7 ft door — older 12 rib, 9200 and 9500
06 41A3589-1 Belt assembly, 8 ft door — older 12 rib, 9200 and 9500
06 41A3589-2 Belt assembly, 10 ft door — older 12 rib, 9200 and 9500
06 41A5434-11 Belt assembly, 7 ft door — T-rail units
06 41A5434-13 Belt assembly, 8 ft door — T-rail units
06 41A5434-14 Belt assembly, 10 ft door — T-rail units
07 041B5424 Belt pulley bracket
07 041A3588-1 Belt pulley bracket — older 41A3589 belt units
08 83A11-2 Rail grease
09 041B4103 Belt tensioner assembly
10 109B33 Trolley belt clip
11 041A5665 Rail assembly, square rail
12 144C54 Idler pulley, wide, belt drive
13 041C5141-1 Trolley
14 12D598 U bracket adapter
16 041B0035B Curved door arm
17 4178B0034B Straight door arm section

Rail Parts Not Shown on the Diagram

Ref Part # Description
— 2777BD Complete belt drive rail assembly, 7 ft door
— 2778BD Complete belt drive rail assembly, 8 ft door
— 2770BD Complete belt drive rail assembly, 10 ft door
— 041A6689 Threaded shaft, D shape, belt retainer
— 041B5669 Belt clip and link
— 041A2848 Rail assembly hardware kit
— 041A2770-17 Installation hardware kit
— 041A8094 Door arm kit — curved and straight sections
— 041-0136 Safety sensor eye kit — current production
— 41A5034 Safety sensor eye kit, 1997 onward — replaced by 041-0136
— 041B0873 Safety sensor sunblocker bracket
— 041A3504 Antenna extender kit
— 041A3504-1 Antenna extender kit with adapter
— L6950 Multi purpose spray lube, green
— L6960 Multi purpose spray lube, blue