It dissambles like RJ utube I do not think Shimano made the tool for sale you have to make it out of a socket it unscrews clockwise the innards look like RJ u tube. If it isent laced to a wheel, will be verry dificult to remove. dissamblr the axel , remove the drive side seal (be carfel you dont bend it) loosen the race then loosen the freehub body and remove. put it over a large pan and remove the race. remove the body. You should get a small jar of Drumonde free hub grease at the LBS to reassemble it. If you use regular greese on the palws they might stiick in cold wearher. good luck