Possible hub failure

[buzzard616]

Two years ago the right rear hub on the signature TT sheared off just inside the outer bearing after being cool to the touch at a stop 45 min earlier. Failure occurred on a hair-pin turn entering the campground so no further damage was done.

Yesterday while checking tire/hub temps at a stop I found the right front dust cap rolling around in the wheel cover. I cleaned it out and tapped it firmly home only to find it loose again 20 min later.

Has this happened to anyone else? I've never had a dust cap fall off anything before! Is there something I need to know about 2000 ALKO hubs? We bought this TT in 2011 with 75 miles on it. It was on a permanent lot for its first 10 years so the running gear is not exactly 'high mileage'.

Hopefully,

Stu

[buzzard616]

Wrap up.

Finally pulled the hub with the runaway dust cap. Found the bearing race for the outer bearing (which was originally pressed in place) flopping around madly in a groove it had worn in the hub. This would eventually have resulted in a hub failure identical to what had occurred the year before. I replaced all three remaining Alko hubs with the same Dexter hubs as the original failure. The Dexter hubs are MUCH heavier than the original Alkos.

I don't know what I may have done or not done to cause this. I replaced all the bearings three years ago. The ones on the right side failed, the ones on the left were fine. (but I changed the hubs anyway)

Made it here to my daughter's place 400 km/240 mi from home with four wheels WITH dust caps still under it and all bearings cool to the touch.

:B

(i think there's a beer left......)

[buzzard616]

So here I am back home. The offending dust cap didn't last the first forty minutes so I tossed it in the back of the truck and continued home.
On inspection this morning the wheel/hub assembly had a lot of play. Maybe that vibrated the cap loose? I was raised 'finger tight and then back off to the first split-pin hole'. In this case that lead to about 3/4" of play at the tread.
So now it is turned on firmly finger tight and pinned there.
Off again tomorrow for a four hour trip. We shall see....

Stay tuned.

Stu

PS
to answer j-d's question; the HUB sheared about halfway between the outer end and the wheel flange. Pretty much left the outer bearing and races intact and relatively undamaged.
Drove to a parts store, ordered a complete hub including bearings, etc, bought a tube of grease and was ready to go a couple days later.

[profdant139]

j-d, I did get the bra. But I am still going to take my trailer to my local mechanic next spring and get the bearings repacked, the brakes inspected, etc., just like I do every year. This is probably over-kill, but I am one of those "better safe than sorry" people.

Plus, we do a lot of very dusty/muddy towing, with lots of rocks and ruts -- so I am extra-careful.

[j-d]

eHoefler wrote:
A hub cap that keeps coming off usualy from a loose wheel bearing allowing the hud to wabble.

No doubt... Some of the smaller trailers, like boat trailers, use very flimsy hubs. A trailer shop told me that installing a new bearing race but getting it cocked/crooked can stretch the dust cap or seal mounting surfaces. So loose cap or loose seal. Hopefully travel trailer/fifth wheel axles use tougher hubs.

[eHoefler]

A hub cap that keeps coming off usualy from a loose wheel bearing allowing the hud to wabble.

[j-d]

Good thing about Bearing Buddy is it's machined from solid metal, not stamped from sheet. What's more, it DOES what it claims, keep water out of trailer bearings. I was doing bearing work a couple times a season on a boat trailer. One time, I cleaned the bearings, greased and installed a pair of BB's. All I had to do for the next 8 years was grease the BB's.

But two things... You may want the inner seal kits that add a stainless seal surface to the inboard ends of the axle. It's essential on boat trailers, probably not so with travel trailer. Hopefully you won't get into water deep enough to rust the axle seal surface! But if you find that surface has gotten pitted, you can use the BB kit to keep you from squeezing grease into your brake area. Second thing, and this you DO NEED! The BB "Bra" kits. Part of the magic of BB is the Spring. It keeps pressure on the grease and it also strokes outward to relieve pressure if you try to add too much grease. That's why you can't blow your inner seal out of the hub while greasing. BUT BUT BUT if the spring are loads up with road grit, the piston can no longer move freely and the BB can't do what it's designed for. Bra keeps the dirt out.

[profdant139]

I had the grease cap on my trailer's hub fall off last week, on a very rough dirt road. I limped into town and bought a set of Bearing Buddys. (I know about the bad reviews, but that is all they had in stock.) Easy to install. I also bought my very own grease gun and was careful not to put in too much grease.

We will see how well it lasts.

[j-d]

Here's a Spindle (same as end of an Axle) and here's a Hub

What Sheared Off? Where?

[westend]

buzzard616 wrote:
I grew up with boat trailers so I realize the need to take care of bearings. I've also had more than one car with non self-adjusting drum brakes so I'm OK there as well.

What got my attention was that one hub sheared off just inboard of the outer bearing so cleanly that it could have been cut and a dust cap that falls off after like a year and a half. I did not see any evidence of contact between the spindle, nut, or split pin and the cap. I did flare the open end of the cap with a pair of pliers before I put it back on so we'll see if it's still in place when we get home tomorrow ( about an hour and a half )

If I remember correctly the dust caps that came with the bearing kits I used in 2014 would not fit the hubs. No amount of hammering was going to make them go in so I reused the old ones. All the other ones are still in place.

I've had them where an ill-placed hammer strike bent the cap enough not to seat. The good news is that they are cheaper than a bottle of beer.

[buzzard616]

I grew up with boat trailers so I realize the need to take care of bearings. I've also had more than one car with non self-adjusting drum brakes so I'm OK there as well.

What got my attention was that one hub sheared off just inboard of the outer bearing so cleanly that it could have been cut and a dust cap that falls off after like a year and a half. I did not see any evidence of contact between the spindle, nut, or split pin and the cap. I did flare the open end of the cap with a pair of pliers before I put it back on so we'll see if it's still in place when we get home tomorrow ( about an hour and a half )

If I remember correctly the dust caps that came with the bearing kits I used in 2014 would not fit the hubs. No amount of hammering was going to make them go in so I reused the old ones. All the other ones are still in place.

[westend]

I'd suggest to pull that hub and any others that haven't been serviced recently. Repack the bearings,clean up inside and inspect the brakes. You will feel better knowing what is going on inside those areas than always wondering when the next one will fail. 10 years in storage means they need service.

If the dust cap doesn't remain seated, buy a new one.

[phillyg]

sfpcservice wrote:
If it's one of the stamped pound in dust caps, sometimes they don't like to be replaced and you have to use a new one. Have you checked to make sure there is no wear on the axle, castle nut and inside of the dust cap that would indicate a hard part pushing the dust cap off?

This.

[Diesel_Camper]

If it's one of the stamped pound in dust caps, sometimes they don't like to be replaced and you have to use a new one. Have you checked to make sure there is no wear on the axle, castle nut and inside of the dust cap that would indicate a hard part pushing the dust cap off?