Trailer Bearings grease

Ray Bowles · Jan 21, 2011

The standard boat trailer wheel hub and wheel bearings are almost universally the same and are available at most Wal-Mart stores or boating stores.
There are 2 wheel bearings on each wheel and a total of 4 for your single axle trailer. If the grease is leaking out the back of the wheel hub then the rear seal is worn out or has been blown out by too much grease being pumped into the hub through the grease fitting on the bearing hub cap. Most front hub grease caps are the hammer in type you mentioned while after market types have grease fittings in the center. If the cap has been hammered on crookedly it can make it out of round and cause leakage or it was one that had a fitting in it and that has fallen out. I install the grease caps with a rubber mallet but a hammer will work IF you hit the cap squarely. If it starts crooked pull it off and start again. Then install the fitting.
If you have never packed wheel bearings, installed new bearings and races or tightened up pre-load on bearings then I VERY highly recommend you have assistance doing this. There is absolutly no room for error doing this as a lost wheel will be the result. Also when replacing a pair of bearings the included races MUST be installed at this time.
Hope this helps. Ray
PS. Never install bearings dry and then pump grease in through the fitting. The bearings will burn up and seize resulting in the wheel passing the tow vehicle. That is really embarassing.

John Nantz · Jan 21, 2011

I'd second Ray's comment....

Very good reply, Ray.

I'd second you're comment about packing the wheel bearings:

Ray Bowles said:
If you have never packed wheel bearings,.....

There is a technique in doing this which would be too difficult for me to explain via a post.

Perhaps swinging by a junior college auto shop class where they work on peoples cars and asking one of the instructors to explain it with your bearings and grease in hand (ummm... pun intended?) might do it. ???

Plan B: just found some youtube videos for "pack wheel bearing": http://www.youtube.com/results?search_query=pack+wheel+bearings&aq=f
but didn't watch any of them because I'd get timed-out.

Dan Hill · Jan 22, 2011

There are 2 sets of tapered roller style bearings in each wheel. The grease is held in by the wheel seal on the inboard side "back" of the hub and the grease cap or bearing buddy on the outboard side of the hub. If grease is escaping from the outboard side you have a cap that is not sealing properly, probably from repetitive installations during axle bearing maintenance. The caps as stated above are press fit and they do wear out after several installations.

To measure your hubs for proper bearing buddies, you will need to remove one of the outboard grease caps. You can either meassure the shoulder that presses into the hub or measure the inside diameter of the hub where the cap presses in. I'm guessing you will find it to be 1 3/4" or 2". Keep in mind, bearing buddies do NOT lube your bearings. They create a positive pressure inside the hub so that when the warm wheel hub hits the cold water at launching the water is not sucked into the hub.

In regards to bearing preventive maintenance. Depending on usage, I do mine every 2 years because I keep "garinion" in a seasonal slip. You should remove and repack your bearings and replace the inboard wheel seal. The seal is pressed in and has to be pried out to remove the inner bearing so it should never be reused. Before packing new grease into the bearing, thoroughly clean out the old grease and check them for pitted rollers, flat spots and any signs of excessive heat. Inside the hub where the bearing makes contact is whats called the race. The bearing and race wear together and become a matched set so never put a used bearing back into a different location. With this in mind never install a new bearing against a used race, this will cause overheating due to reduced contact area. The race is also press fit into the hub. Bearing, races, and seals are "usually" marked properly with manufacturers part numbers and can be purchased in kit form and individually. Not all brands and manufacturers of these products are the same and I personally would not trust this type of product from any place with "mart" in their name. Go to a reputable auto parts store of your choice.

Good Luck

dscribner · Jan 22, 2011

Replace the bearings with new, freshly packed ones. It's about 1 1/2 hours to do if you don't know what you're doing (ask me how I know). You'll have no slinging grease and peace of mind. The cost is probably $50 or less.

Unless it's much different from my EasyLoader:

1) jack
2) pull the wheel
3) pull the cotter pin
4) remove the nut
5) remove bearing
6) slide on new bearing and reassemble

I "saved" money by not replacing my rear hubs on my 1885 trailer. (I replaced the front and brakes). One day as I entered the ramp area, all my lug bolts (not nuts) stripped out and that tire was wobbling at about 20 degrees. I should have replaced it when I knew it was old. I replaced both hubs including lugs (nuts this time) and bearings for $70. Certainly worth the money and trouble.

dscribner · Jan 22, 2011

OOps! That's a 1985 trailer!

c_witch · Jan 22, 2011

greasing wheel bearings

Hiee,

It sounds like the bearing cap is dented and not sealing tightly. There are 2 bearing on each wheel and inner and outer.
1 Jack up and block axle and remove tire
2 Remove bearing cap by 'Gently' tapping on edges all the way around
3 Remove carter pin in axle that runs thru nut
4 Remove nut
5 Slide hub assembly from axle
6 Remove outside bearing
7 Flip hub over and gently pry out grease seal
8 Remove inner bearing
9 If right handed then load a big glob of grease in left palm take bearing in right hand between thumb and forefinger and and slap it into glob of grease all the while 'slowly' rotating it. You will see the grease gradually penatrate the rollers to the inside. Make sure there is lots of grease in the rollers and not just on the roller cage.
10 Replace inner bearing and 'Gently' tap NEW grease seal back into place
11 Reverse order for the remain re-assembly
12 Use a NEW cotter pin in the wheel nut
c
*Edit*
When replacing the wheel nut do NOT over tighen;however, it should not be loose either. I'm not sure of the torque but think 15 lbs or so. Check a manual on that one. Tightened to much and the bearing will burn out. Not tightened enough and you will loose a tire completely while driving down the road

*End edit*
A very simple bearing greaser can be built as such. Take 2 very big flat washers 2 or 3 inch diameter. drill a hole in the outer edge of one of them. Drill and tap one of them on the outer edge to accept a grease nipple. Do you see where I am going with this yet?? No ok using a bolt put one washer on one side of the bearing and the other on the other side and bolt together use a wing nut its easier. Now simply use a grease gun and pump grease into the fitting. When the grease is oozing out of the outside of the bearing you are done. Still just as messy as using your hand but does a much better job of getting the grease into the roller cage and onto the rollers.

Brina

Mark H said:
The boat trailer I have, I believe is the orginal 1993 Hunter.It is single axel with no brakes.
The port side of tire keeps throwing grease out onto the wheel. There is no grease on the back side of this wheel.
The starboard side has no problem.
The way I understand it the bearing is only located on the back side. So the cap on the front must be allowing the grease leak?
Has anyone had simular problem? Thank you in advance.

Also question number 2....How can I find out what size bearings/ buddie caps should I buy? My bearing cap on front of wheel does not screw in.It is just driven on with mallet.

r.oril · Jan 22, 2011

Polymer

As my neighbor explained to me: Bearing grease is a polymer that holds oil. The bearing heats up, melts the polymer and releases the oil. Over packing the wheel is just as bad.
I hand packed my bearings this week in preperation for Havasu. I plan to drag the boat into town (35 miles) next week to test out the packing job.

timebandit · Jan 24, 2011

Hints
If you replace the washer and nut back on the spindle after removing the outer wheel bearing(and before removing the hub) a few quick jerks of the hub and the rear bearing along with the seal will be left on the shaft. Usually you can reuse a seal once this way and it is way easier than prying out the seal.

Do not grease the inside of the bearing or the shaft which it rides.

If you have to knock out the old bearings look for a notch to place the punch so you can hit the race (from the other side of course). When installing a new race use the old race aginist the new so that you don't hammer directly on the new race.

Use "wheel bearing grease" not general purpose or chasis grease.

Winkfish · Jan 24, 2011

Make sure you have standard sized bearings. I recently had mine serviced, and they were not standard. The shop, a very reputable one, had the right sized bearings and fittings, but not the right sized seals. They gave me the number of a couple of bearing wholesalers to save me a couple of $$, and I ordered the seals myself.

kenn · Jan 24, 2011

There's a nice post with pictures here on bearing replacement. I serviced our trailer two years ago with these instructions.

It explains very well how to preload the bearing with grease before assembly. Buy some latex gloves, you'll need'em.

jimmyb · Jan 24, 2011

kenn said:
There's a nice post with pictures here on bearing replacement. I serviced our trailer two years ago with these instructions.

Good article except as a former mechanic I would never install a new race with a screw driver. The best way would to press in with hydrolic press or tap in but use a piece of faced round stock just under the ID of your hub. If you dont have any round stock try to find a socket that is just under the ID of your hub but still large enough to bear against the full dia. of your race. This will distribute the load of hammer blows and will be easier to keep the race square to the bore of the hub. Races are hard material but somewhat brittle. One bad blow or slip of the screw driver may chip or score the new race. You will know when your race is fully seated when you hear the tone of the hammer blows change from a tinny ring to a solid clunk. Sounds funny but trust me you will know.

Do the same with the seal. Find something round to support the full dia. Wood or plastic will work with the seal as it will go in with much less effort. Keeping them going in sqare to the bore is the trick. As the author suggested seals will damage easily.

just me 2cts, jimmyb

dscribner · Jan 25, 2011

Nice posting Jimmyb.

How're things in Mass?

Sumner · Jan 25, 2011

Get the above set....

http://www.harborfreight.com/bushing-bearing-set-38145.html

....and it will make putting in seals and races really easy.

I hate to give advice on putting in bearings. It is so easy to do, but also so easy to get the tension on the bearings wrong by over-tightening the spindle nut. You will tend to think they are too loose and then over-tighten. The best thing is to have someone you trust to show you the first time or take the time to read or watch some videos as the guys have pointed out.

Spend a couple dollars more and go to the auto parts store and get marine wheel bearing grease. Put bearing buddies on and use them as per the instructions,

Sum

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kenn · Jan 25, 2011

jimmyb said:
Good article except as a former mechanic I would never install a new race with a screw driver.

Yeah, good point.

Sumner said:
It is so easy to do, but also so easy to get the tension on the bearings wrong by over-tightening the spindle nut. You will tend to think they are too loose and then over-tighten. The best thing is to have someone you trust to show you the first time or take the time to read or watch some videos as the guys have pointed out.

Spend a couple dollars more and go to the auto parts store and get marine wheel bearing grease. Put bearing buddies on and use them as per the instructions

All good points. From doing bicycle hubs and one front wheel bearing, I learned where "tight enough" is, and with practice it becomes simple to tell when the wheel starts to bind and it's time to back off the spindle nut.

After any bearing work, I always try to check the trailer hubs after about the first 10 miles of loaded towing - if the hubs are more than just slightly above air temp, there could be something wrong.

jimmyb · Jan 25, 2011

dscribner said:
Nice posting Jimmyb.

How're things in Mass?

Don, how are you? Things have been rough around here lately. Mom has had a bad stroke about a month ago and I have been very busy looking out for her, visiting everyday in rehab. She is getting decent care and working hard to get back home.

Other than that it is winter as usual. Got to -20 here night before last at westover airforce base in chicoppe ma. Wont stop snowing here either.

Hoping things get back to normal in the spring so we can get out sailing again. Would like to upgrade the boat but all the ones im liking are in fla right now. Just my luck eh.

God Bless ya Don, jimmyb (my apology for posting this here. just to tired to do otherwise)

Barry B. · Jan 25, 2011

Latex Gloves???

Rather than using latex gloves I would recommend using Nitrile gloves unlike latex they are resistant to most chemicals and are useful for many boat repair and maintenance projects including using epoxy.

kenn · Jan 27, 2011

Barry B. said:
Rather than using latex gloves I would recommend using Nitrile gloves unlike latex they are resistant to most chemicals and are useful for many boat repair and maintenance projects including using epoxy.

Nitrile = synthetic latex

But yeah - nitrile are better.