I have a leaky Rear Pinion Seal on my 2006-2500 4x4. does the shaft nut use a crush sleeve or do you just torque it down. I'm trying to decide if I should do the repair myself. I have never replaced a pinion seal and do not want to burn up a bearing. I have done my own locker installation on my Samurai so i'm not incompetent, unless you ask my wife.