When performing the 12-month/800 hour lubrication of the H-Stab actuator (Task 27-40-01-640-801), make sure to use the proper grease gun adapter and correct technique to avoid rejection of the actuator due to it not taking grease.
Some grease needle fittings are too long and sharp and will push the high pressure ball into the fitting, closing off the port.
Similarly, when electric grease guns are used, the high nozzle pressure trying to force the grease pushes the ball into the fitting and closes the port. This does not allow the grease to enter and makes the technician believe the actuator is faulty.
Do not use electric grease guns!
Proper tools and slowing down the greasing action wins this race.
Falcon 900 and Keeping your Cool
Falcon 900: Closing the Baggage Door