[chopper]

427 S/O:

I would agree that the crush sleeve was used to set bearing preload IF the adjustment was set solely via some amount of torque on the spindle nut during the preload process. However, the adjustment procedure (at least the one used in Haynes and verified by a local Britcar mechanic) just requires the nut to be tightened (which necessarily crushes the sleeve) until there are 4.5 to 5.5 in-lb of rotational resistance between the spindle and the mounting plate, just like the preload you'd put on the front wheel bearings. Logically, I could set that preload up with or without the crush sleeve in place, and still have the axial movement controlled by the thrust bearings. I'm not saying you're wrong, I'm just saying that reason doesn't make sense to me since I can set the proper amount of preload with or without the sleeve. From that, I sort of concluded that the function of the sleeve more logically is to prevent migration of the inner bearing races once the bearings start to wear. I've spent some time puttering around the websites but haven't uncovered any engineering-type explanation for the inclusion of the crush sleeve in this application.