The special tools needed are a four prong socket for the new lock nut, about $15 at your local parts place(I got mine for $12 at PEP Boys), you will need it later to do any service on the front axle/hubs so its a good thing to have. I didnt have the socket for the existing lock nut, but I used my clamping vise grip to get it off -worked great! The vise grip with the big C clamp jaws-used alot to hold things while you work, they are a must have in any tool box.
Took me 2 hours including repacking the bearings
Steve