I like Shimano hubs. The cup and cone bearing system is the best one out there. Smooth and serviceable, least amount of resistance compared to other cartridge bearing hubs. They do have one caveat though...... the freehub bodies are total fucking shit. I've destroyed quite a number of them over the years and am use to replacing about two a year on average. I even keep a personal stock of freehub bodies to keep me going, just in case the supplier is back ordered. To be fair though, I've also ruined the likes of DT Swiss and Ringle freehubs too.
A recent ride took out another one on me, I decided it was time for a garage file on replacing and tuning your shimano hub.
Above you can see that my freehub is totalled. Time to rip into it.
Remove the rear wheel from the bike and get the cassette off. On this particular model of hub I had to remove the brake rotor as well (centerlock).
Get your cone wrenches out and break the locknut loose on the non-drive side. Remove the cone from the non-drive side and pull the axle out the drive side. Working with the non-drive side is easier as you can get a firm hold on the nuts without interference.
Now place everything on a rag and keep it organized, clean and set aside. Be sure to note how many bearings are in the hub, this model (like most Shimano) has 9 bearings per side.
Use your big 10mm allen wrench and remove the freehub body.
Grab the new freehub body, make sure to reuse the washer behind the original freehub body (if equipped). Grease the threads of the freehub retaining bolt and install after cleaning the hub face.
Now pack the bearing cups with grease and install the bearings one side at a time. I do the drive side first then slide the axle though to hold the bearings in place when you flip the wheel and work on the non-drive.
Now install the non-drive cone and lock nut. Tighten the cone with your fingers only then install the lock nut. Now put your 17mm cone wrench on the lock nut and use the 15mm cone wrench to TURN THE CONE BACKWARDS INTO THE LOCKNUT! Just snug it up. Don't go crazy here. Now grab the axle and you should have a little bit of play in the bearings. Use the 17mm cone wrench on one side and a regular 17mm wrench on the other and slowly tighten the nuts, this will rotate the entire locknut / cone assembly on the non-drive side. Turn it just enough to get the play out of it, the axle should spin freely.
All done, just put the cassette back on and the rotor, put the wheel in the bike, double check your brakes and shifting, adjust if needed. Easy as that. Shimano hubs kick ass, just wish they could build a freehub body that wasn't made from cheese.
The Bric...._ mountain biker, road rider, heavyweight gear abuser. Built like a brick sh*thouse. No bike is safe.