View Full Version : Trailer hubs

05-06-2011, 03:01 PM
Just got my boat back from a dealer. They changed the oil in my hubs and I noticed they are not completely full. I don't remember them being like that before. I called them and they said that is how they should be, that when they heat up it will expand and blow a seal out if it is completely full. I checked the owners manual and it says they should be full ?????

05-06-2011, 03:32 PM
how do you even check the oil level in the hubs?? and i would imagine that as long as they are half or a little over it will be fine, the bearings will get lubricated via splash and spray

05-06-2011, 05:25 PM
The end of the hub is clear on mine. You can see the oil level. It appears they are about half way full.

05-07-2011, 09:27 AM
On the clear hubs you only need 1/2 and you really dont want any more then that.

This is the same way the axles on your truck work. If you craw up under there and take off the fill cap and stick your finger in there you will notice its only 1/2 full. This is for several reasons.

1 you need room for the fluid to expand as it heats up.
2 fluid doesnt compress and if it was full then the gears wouldnt have room to spin and you get Hydrolock.

On the axles for the trailer it works the same way.

As for RD i have the same year trailer as you and i cont have the clear caps eighter. Mine are silver in color with a logo on them.

In this case you just need to keep your rims clean and each time you go out look at your rim and make sure theres no oil on your rims.

As for towing with these types of axles, any constant liquid filled axle and espeacial ones with Brakes. DO NOT DIP IT HOT.

This means come down the big hill just before the ramp and then back it right into the water. You will here sizzleing and then the dead POP and see all the fluid running out of your axle.

You really need to give the axles a good 5 to 10 to cool down. I do the touch test or the spray water test on mine especialy after a long decline to the ramp.

I wet my finger, spit works well, touch the rim and if its Hot then wait a good 10 minutes. Or spray a little water threw the rim onto the brake and if it sizzles wait a good 10 minutes.

This will save the axle seals and help keep from warping the brakes from dipping them into cold lake water.

Last year at Lake Billy Chinook i wastched 3 different people over 2 days blow axle seals and probaly ruin there breaks because they dont want to let stuff cool down after the 3 mile decline down the mountina into the valley.

We generaly pull into the loading prep area and get all the gear on the boat up in the racks, use the restroom, make sure we readdy to go. This takes about 10 minutes then when im about to hit the water with the trailer i back it in very slowly so if it is still warm its not a complete shock to the trailer.

Love your trailer and take as good of care of it as you do your boat, because when it fails your boat, your rig and you are in serious danger.

05-07-2011, 09:31 AM
According to the manual, the hubs should be full. I think I read somewhere that any air in the hubs will get hot and expand, raising the pressure in the hubs.
It is easy to do. Take the tire off, spin the hub around until you see a set screw at the top, remove the screw and fill it up. It uses 50w motor oil. Don't mix viscosities.
If you don't have a manual you can download copies for the hubs, coupler and brakes from the Trailer Buddy site.

05-07-2011, 11:21 AM
Thanks Mmandley this is what I have been told after doing a little more research. Like Nibots said the owners manual says they should be full. So the answer is clear as mud.

05-07-2011, 01:11 PM
It seems like standard oil hubs and the vault hub are different.

They claim to have a "hybrid oil" which is thick like grease at ambient temperature but thins out too a heavy weight oil as it is heated by trailering. the want it filled completely as the pressure that builds up helps keep other thing out of it, and there are springs on the seals so that if had room to expand and can regulate the pressure.

05-07-2011, 11:22 PM
I usually fill them all the way except leave a little bubble of air at the top. This allows an easy reference to see air and oil. Sometimes the clear lense needs a wipe to clean off the road grime.

05-09-2011, 04:28 PM
Sent an e-mail to boatmate and received a response right away. I was told that yes they need to be completely full. Just an FYI.

05-19-2011, 02:47 PM
So do all boatmate trlrs have these kind of hubs? I have an 07 LSV with a boatmate trlr and no clear window, But there is a silver cap but I don't recall an emblem on it? I do remember seeing a screw on top o the hub though.

I was thinking I needed to re-grease my hubs but maybe the oil just needs to be checked?

05-20-2011, 09:17 AM
My 08 tailer has the V sticker on the hubs and you cant see in them eighter. I assume as long as nothign is leaking im good to go. I soppose i should find a way to check them. This will be the first season that the dealer hasnt looked at the boat and trailer.

05-20-2011, 02:48 PM
i just replaced my right front brake caliper on my trailer yesterday. it had UFP calipers and of course no one in Houston sells them and I do not have time to wait to order them so I bought Kodiak. Well Kodiak did not sell just a caliper so I had to buy a whole kit, so now I have 3 Blue UFP calipers and Hubs and one Zinc coated Kodiak caliper and hub. couldnt get any of the "hybrid" grease vault uses so we just packed the new bearings with regular red wheel bearing grease....

05-20-2011, 02:58 PM
^^^was it not still under warranty ?

05-20-2011, 03:00 PM
I just picked up some 50 weight oil for my hubs. Mine aren't the new Vault ones. I noticed a trail where some has ran out on one of them, my bet it I wind up having to order a new rear seal, but hopefully this will get me by for a few more weekends and I have time to pull it apart.