912 ULS Gearbox Life Limited Parts

All components within the 912UL, 912ULS, 914UL, 912iS, etc gearboxes are "on condition" and are replaced only when necessary. If the propeller shaft is removed, then the prop shaft bearing and seal require replacement. 

The torsion shaft in the 915iS gearbox is replaced after a certain amount of hours of operation (currently it is replaced every 600 hours)