greasing trailer wheel bearings

tawilson · Apr 27, 2005

I've got 4 trailers(boat, snowmobile, dump and equipment) and would like to get up to date on greasing the wheel bearings. First, some of them have the zerc's on the grease caps. Is that adequate for lifelong greasing or do you still need to pull the wheel and get your hands dirty? Second, anyone care to give a quick run through. I used to do it at my dad's trailer sales 25 years ago, but could use a refresher. Is it necessary to pull and replace the back grease seal, or is just pushing the grease in with the fingers enough?

Bird · Apr 27, 2005

Tom, I guess it depends on where those trailer hubs have been and for how long. One of my brothers had a 17' boat on a trailer in Alaska; used it both on fresh water lakes and in Resurrection Bay out of Seward. I think it was 4 years old when he moved back to Texas and brought it with him. It had the bearing buddies, so he could just hit them with the grease gun. However, when it was about 6 years old, we decided to take it to the Texas coast to go fishing and decided we might ought to pull the bearings first to see what they looked like. Good thing we did, too, because all the bearings and races were in bad shape, so we replaced everything. Personally, anytime I repack wheel bearings, I use new seals. You can't get the inside bearing out to properly clean and inspect it without removing the grease seal. You might replace the old seal and be OK, at least if the trailer doesn't have brakes, but if it does have brakes and the seal leaks, then you have a brake job to do, too.

So . . .,

1. pry off the cap (if it has bearing buddies, tap lightly around the outside with a rubber or plastic mallet to loosen and remove them),

2. then remove the cotter pin (I like to use a new one when I put it back together),

3. unscrew the castle nut, pull the wheel, or hub, outward a little bit, then push it back, and you can easily remove the outer bearing and washer,

4. I usually put the washer and castle nut back and jerk the hub off (that lets the washer and castle nut knock the inner bearing and seal out of the hub (some prefer to just pull the hub off after step #2, then pry the seal out),

5. Clean everything thoroughly in solvent, dry it all, and inspect for pitting or other damage, (if there is any, buy new ones),

6. Pack grease into the bearings,

7. Put the inner bearing into the back side of the clean hub,

8. Press or drive the seal in, being careful to keep it straight (I sometimes use a clean wooden block on it, being careful to not get any splinters or sawdust in the hub),

9. Finish installing in the reverse of the disassembly.

And, yes, it's a dirty job. /forums/images/graemlins/frown.gif

RedRocker · Apr 27, 2005

I'd do a repack like Bird said regardless of the bearing buddies. One of my trailers has them and after a few years it was due for a good repacking.

tawilson · Apr 27, 2005

Thanks Bird. Neat trick for getting the inner seal out. I figured prying it out would probably damage it.

Darellk · Apr 27, 2005

As a car mechanic in a former life I've packed thousands of wheel bearings. I found the greatest invention since sliced bread for doing it. It is a plastic bearing packer readilly available from a tool truck or maybe napa parts. Fill the container with a good quality bearing grease drop in the plunger. The top is cone shaped so you just wipe off the old grease on the bearing,place it in the packer, install the cone top and press down untill you see new clean grease coming out of the bearing. It is a huge time and mess saver. I can pack 4 bearings in less than 5 minutes and hardly get my hands dirty. I think the manufacturer is Lisle Tool.

tawilson · Apr 27, 2005

I remember that. My dad had a metal one. Thanks for the advice guys. As a reward, here's a link to one of the funniest clips I've ever seen. reptileattack

Bird · Apr 27, 2005

You mean sorta like one of these? I gave mine away when I moved back to town.

Alan L. · Apr 28, 2005

Since I have not had time to fix my trailer I took it to a trailer dealer where they are rewiring it, putting on all new lights, new boards, welding on a new bulldog coupling, and repacking the wheel bearings.

The trailer is 6 years old and I have never repacked the bearings, so I wouldn't be surprised if the bearings are shot. The mechanic told me they take them off, clean them up, and spin them with air. If they survive they keep them, bad ones will fly apart he said.

RedRocker · Apr 28, 2005

( Thanks Bird. Neat trick for getting the inner seal out. I figured prying it out would probably damage it. )

You need to replace it anyway, so pry away.

Egon · Apr 28, 2005

( Clean everything thoroughly in solvent, dry it all, )

Bird:

Many years ago we were given a talk on lubrication by a company representative. He specifically said not to use air to dry any bearing cleaned in varsol as it would affect the grease's ability to stay attached or coat the metal.

Egon