Sully,
Pretty easy actually. Just take your time and do it carefully.
1) Remove whatever cap / grease fitting mechanism you have on the outside - Bearing buddy, etc... I use a rubber mallet, tapping on the sides of the cap / BB with the force extending out away from the trailer. Tap, move, tap, move - as you rotate the wheel. You will see it "walk" out of the hub.
2) You should have a cotter pin holding a castle nut / washer - remove it and chunk it in the garbage. Some people say to reuse the cotter pin. At less than .50 cents, I'll just replace it for the peace of mind. Remove the nut / washer - the hub should now be free to come completely off of the spindle.
3) Front bearings should just fall right out of the front. Place them somwhere clean
4) Take a large flat blade screwdriver and go from the front of the hub to the back, placing the screwdriver blade tip on the rear seal ONLY (make sure it's not touching the bearings). Whack it with a hammer, moving it around the rear seal until you punch the seal out of the back of the hub. Destroying the seal is fine - you aren't ever going to reuse a seal that you removed anyway. Just make sure you don't hit the bearings with the screwdriver.
5) The rear bearings should fall out the back like the front ones did once you get the seal removed. Place them somewhere clean too.
6) Clean everything out of the hub the best you can and inspect the races inside on both the front and back (the angled cone surface inside the hub that the bearings ride on). Make sure they aren't worn. If they are - you should replace both the races and bearings, as I'm sure the bearings are worn too. Probably won't be the case - but while you have it all apart - check it. Check the bearings all the way around to make sure they aren't worn. If not, then you are ready to put everything all together again.
7) Repack the bearings - don't skimp. They are out and free right now, so do it. I use a bearing packer that I purchased for about $10 from Autozone, and it works really well. Make sure that by the time you are done, the bearings are completely full of new grease.
8) Now smear a large dab of grease into the hub on both sides where the races are and put the rear bearing back in (make sure it's facing the right way
). Now lay the new seal, with the flat portion exposed up towards you like the original was, on the hub. Lay a small piece of wood (a short piece of 2x4 works great) over the seal so that it is flat. Slowly tap the wood with your rubber mallet until the seal seats into the hub recess.
9) Turn the hub over and place the front bearing in (make sure it's facing the right way again!). Place the hub aside in a clean place.
10) Check the axle spindle by wiping it clean and checking it carefully.
11) Place the rebuilt hub back onto the spindle, making sure the front bearings don't fall out.
12) Replace the washer, castle nut and retighten. I always "seat" everything by tightening it just enough so that the hub gets hard to turn, and then back it off completely. Then retighten the nut so that it is "snug". The hub should not have any play back and forth, and the nut should be just a hair past "hand tight" on the spindle. Replace the castle nut washer (if equiped), and put a new cotter pin back in place. You might have to move the nut a hair one way or another. I always air on the side of a hair looser than a hair tighter - as long as you don't put play into it. You should be able to come to a happy medium in placing that cotter pin.
13) Replace the cap / Bearing buddy by placing that piece of wood you used to seat the rear seal - and do the same to it - smack it slowly with a mallet until it seats.
Always use the flat piece of wood to seat the seals / cap / Bearing Buddy. Don't hit it with a regular hammer or something like that - you will mash them up and they will be unusable.
Hope this helps, and hope it's clear.
All the best,
Glenn
