Hope you understand "Preload" is just that, a temp tightening, then let it off, lock in diff way. On your truck, get one of those big tin sockets to fit your nut. Snug the middle one while turning hub/wheel to about 40 lbs. Then back it off about 1 flat on the nut. It will seem loose. Then put on the locking tab ring with tab in axle and maybe into slot in nut if it was that way before. Don't be afraid to turn nut some looser if needed to line up notch. The second or outer nut is the ONE that needs the torque on it. I just looked in manual and it says back off inner nut 45 degrees from tork. The outer one just says to tighten fully, didn't give torque reading in print or specs. Think you can go pretty high like 80lbs or more. Then bend over a tab on washer into a slot on nut to lock.
If you have nuts that are not hex, there is a special socket for them. I got one, was $70, but fits many years of trucks. Otherwise you are guessing with hammer and punch or big pliers. Most important to make outer nut tight and locked, or both will work there way off and wheel/hub and axle will roll out of truck on a corner or elsewhere.
I see on another post about burning off oil on shoes. That was new to me. I get mine relined, usually $25 to $40 depending on size at a local brake parts shop. I once tried brakleen on some, looked good as new. Once installed, oil bled up from inside farther, and brakes grabbed bad again. I would bet that is what you will get too. Once oiled up, they are ruined. Get new seals too, usually can find them at brake shop or parts houses fairly easy.
