This version of XT gearbox is only for models up to July 2018. Models August 2018 use 64598 and 64599 gearbox.
M8 Thread in shaft.
Important fitting instructions.
Always use thread locking compound (Loctite ™ 277) or similar to M8 bolt when re fitting wheel on gearbox shaft.
Tension M8x20 bolt. Torque = 25 N-M.
Apply small amount of grease to gearbox shaft and hub when re-fitting hub.