Resolving issues with the Residential Jackshaft Operators (RJO and RJO10) travel limits, 3800, 3900, 8500, 8500W, 8500WRGD, 8500WLA, LJ8900W, LJ8950W. While the incidents of improperly functioning units are low, we are extending the warranty for affected customers until September 2023. LiftMaster® Garage Door Opener Model 8500 Owner's Manual To download your product manual, click the following link Download ManualNOTE: The 888LM or 889LM MyQ Control Panel is found on the Accessories page, under Included Accessories in the Carton Inventory section. • High lift (up to 54 inches (137.2 cm) high) and standard lift sectional doors up to 14 feet (4.3 m) high. setting the down position: Push and hold the yellow button until the door reaches the desired DOWN (closed) position. We have resolved the loss of function affecting some of our LiftMaster 888LM Control Panels. These units were packed in with garage door opener models 8500 and 8500C, and/or sold as an accessory, such as MYQPCK. Residential Jackshaft Opener: How to resolve issues with the RJO losing its travel limits. The myQ Control Panel is covered by the Parts Warranty for the 8500 only as its required for the remotes to work. Once the door is closed, if there appears to be too much pressure on the door, you may toggle the door back and forth using the black and yellow buttons to reach the desired closed position. The torsion bar must be 1 inch (2.5 cm) diameter. • 4-6 inch (10-15 cm) drums, not to be used on tapered drums over 6 inches (15 cm). • Doors up to 18 feet (5.5 m) wide.