The LiftMaster 109B48 is a genuine OEM replacement part (trolley threaded shaft) for the LiftMaster 85870 3/4 HP heavy-duty chain drive garage door opener.
Check the parts diagram on the 85870 replacement parts page to confirm the correct component before ordering.
Genuine LiftMaster part — in stock and ready to ship. Call (866) 965-5599 for help.
![Liftmaster 04-41A3489 trolley assy [041A3489]](https://cdn11.bigcommerce.com/s-32eq2wsbti/images/stencil/500x659/products/11719/227178/liftmaster-04-41a3489-trolley-assy-041a3489-04-41a3489__83574.1721407155.jpg?c=2 "Liftmaster 04-41A3489 trolley assy [041A3489]")
![Liftmaster 03-41A3489 trolley assy [041A3489]](https://cdn11.bigcommerce.com/s-32eq2wsbti/images/stencil/500x659/products/7806/233043/liftmaster-03-41a3489-trolley-assy-041a3489-03-41a3489__81958.1724089527.jpg?c=2 "Liftmaster 03-41A3489 trolley assy [041A3489]")
![Liftmaster 01-41A3489 trolley assy [041A3489]](https://cdn11.bigcommerce.com/s-32eq2wsbti/images/stencil/500x659/products/12240/229267/liftmaster-01-41a3489-trolley-assy-041a3489-01-41a3489__00773.1721410504.jpg?c=2 "Liftmaster 01-41A3489 trolley assy [041A3489]")
![Liftmaster 13-41C5141-1 Trolley [041C5141-1]](https://cdn11.bigcommerce.com/s-32eq2wsbti/images/stencil/500x659/products/10095/231985/liftmaster-13-41c5141-1-trolley-041c5141-1-13-41c5141-1__30261.1724087842.jpg?c=2 "Liftmaster 13-41C5141-1 Trolley [041C5141-1]")