Bigger axle needed?

[kcburro]

Moderator's note: this topic was split from the real world trailer weights thread (in General Chat). Alas, the post's original title was lost, but it had something to do with "unobtainium."

Must have bounced off, maybe I have an axle issue!!?!?!?!

Revisiting a previous thread: (http://www.fiberglassrv.com/forums/f...rro-53324.html)

OK. I knew I would be more than the 1100 pound advertised weight based on common sense, and the immediate response of some of you to the above "unobtainium" thread. But I also knew that I would be under the "trailer Weights in the real world" list for a couple of other 17 foot Burros of 2900 pounds. I don't have any gray or black tanks. But where in between would I fall?

I had already weighed the TV on my way to pick up the trailer after the coupler change-out. I mentioned that I was on my way to weigh the whole rig when the technician said, "well I hope it is under 1500 pounds since that is the rating of the axle and the hubs". Uh-oh.

Well, the axle came out at right at 1620 and the tongue weight calculated at 260. So my trailer is about 1880. So the ratio is ok. It isn't quite a dry measure--there is some water and full propane in the tanks. But nothing added by me, yet.

So, did they build the Burro on under-rated axles? Is it likely something isn't original? (new floor? new frame?) Maybe the tech was wrong? I guess I have more looking to do.

I won't be adding much but some basic camping and I won't be towing it more than 100 of miles a few times for the rest of the year, so I'll probably wait until next year to do any serious thinking about an axle replacement. Am I burying my head in the sand or fretting too much already?

[rabbit]

Den, I forget whether your K.C.MO Burro is an Iowa or Kalifornia Burro? The axles under the later Escondido (at least mine) is a Henschen Ind. "Dura-Flex" rated at 3000lb. The Scaleman's small sampling of 17 Burros were around 28-2900lb. curb weight as found which is under the rating and acceptable if you take rating at face value. Are you suggesting that a margin of unused capacity is necessary for axles as it is for tow vehicle and probably tires?

jack

[kcburro]

I have an '85 which I understand to be an Iowa model. I don't know what Burro rated it for, only what a tech told me about the axle on it.

And my weight is over that, before I add any thing. don't know enough whether to worry or not!

[Mary F]

Again, this new topic was split from Trailer Weights in the Real World, for more visibility of Den's question.

[rabbit]

We appear to have our fingers crossed on this one. So I'll venture out on the limb and say that I think the Henschcen 3000# rated axle is what they "felt they could away with" on the 17WB as were the 13" tires and their combined wgt. rating. I'm currently over the axle rating by 100 lbs. I switched out rims and tires to ST205 14Rs with a wgt. rating per tire of 1762 lbs., 3524 combined. 12% margin on the tires at least but 3% over the axle rating. I could lighten ship by 100lb. very easily. The real question is who's responsible for the safety margin? The axle fabricator? The trailer builder? The owner?

Henschen? Possibly as I can't imagine wanting one's product spec'd for use right at the threshold of failure. Burro? Clearly not worried a bit. The owner? Has to be!

Will I be going to a 3500lb axle in the near future. Not until the rubber bands are shot (and after 14 yrs. they show no sign of that).

jack

[Bob Miller]

Original "responsibility" for the axle selection lies with the builder, but that's moot at this point. Basically it's now your oppotunity to be sure it's safe.
But get another source to inspect your axle for it's rating, I doubt if Burro installed a 1500# axle from the start.

A bit of good news, you can deduct the weight of the rims and tires from your total wt. number, they aren't a load on the axle.

[rabbit]

This is the manufacturer's plate on mine. The capacity is clearly stated as 3000#. KC's Burro should also have this rating. Plate is on rear of axle. Unless your underside is a lot shinier than mine, you'll need to burnish off a bit of rust with ScotchBrite, Scrubby, emory cloth to make the embossed lettering legible. I did not mean to suggest that the axle under 17s was grossly underspec'd; certainly nothing like 1500lbs. It wasn't spec'd for comfortable weight margin either unless, as I said earlier, Henschen was conservative in their rating.

You can right click to blow up the pic if it's difficult to make out the wgt. rating.

jack

[David Tilston]

When I purchased my Trillium 4500, the axle was the stock 2000 lbs. The coupler was also stamped 2000 lbs. Since the trailer is about 1700 lbs, totally dry. I felt that 300 lbs was not enough for the load I intend to carry.
I changed the axle to a 3500 lbs unit, and the coupler to a 2" ball. I also added a hitch receiver to the bumper of the trailer. On the way home from the shop that did the work, I went over a bumpy rail crossing. In my rear view mirror, I saw the trailer jump up and to to side. When I got home, the leaf in the table was broken. The table was set up as a bed. I thought that was the safest configuration. Because the part of the table, closest to the wall, is not supported on the dinette seats, the dowels had pulled right out the bottom of the leaf in the table. Now when I take out the trailer, I make sure that I have lots of weight in the trailer.

I think I should have gone with a lower capacity axle. I believe that the manufacture of the axle engineers in extra capacity, the trailer was completely empty and so was no more then 1700 lbs. If I had to do it over, I would have gone with a 2500 lbs axle, or just used the 2000 lbs axle that the trailer came with. It was in very good shape and had brakes.

I guess what I am saying is that I now feel that I gave into fear and regret it.

[rabbit]

I understand completely, David. I wasn't present at the creation either.

jack

[ruscal]

Den,
I would think that a axle rating has a little safety margin built in to cover some overloading. In your case you could take your trailer weight and weight of all carried items and submit that weight to an axle manufacturer to get their recommendation. As I remember Flexiride said to multiply the loaded trailer weight by 125% to get to ideal axle rating. I ordered a 3500# axle for my 2800# Scamp. It rides sweet. Other manufacturers may have their own formula. Ride quality also factors into the picture. If your axle is rated too high your suspension won't move, and the ride will be harsh. The loaded trailer should sag the suspension 25% or so of total travel. You could load your trailer with all your stuff and then put a couple of big guys in the trailer and have them bounce up and down while watching the suspension work to check how much travel is used. If there is adequate travel you should be good to go for the time being. just don't exceed the axle rating. It is hard to stay under 300 lbs when loading!
Russ

Edit: Sorry, I thought your axle was rated 2000. At 1500 you are overloaded with the empty trailer. You should probably just bite the bullet and re-axle.

[rabbit]

I take the statement of Den's "technician" which is quoted in his original post as possibly not good as gospel. Here's why? The original 13" rims and tires would have had a weight capacity of something well above 1400 lbs. apiece. Add the two together and you're pretty close to 3000lbs. capacity. To suggest that the axle and ONE wheel and tire have the same rating is rather strange, don't ya think? I doubt if Sac City Burro put anything less than a 3000lb/rated axle under the 17 footer; I provided evidence that Escondido used 3000 and they have a rep for corner cutting. As previously stated, it is easy to scoot under there with a flashlight and find out for yourself.

jack

[Jared J]

I now the original poster took this into consideration, but for the rest, keep in mind your axle isn't taking the full trailer weight.

[kcburro]

Thanks for the feed back.

I hadn't thought about the weight of the whole axle assembly and wheels being part of the total--so that would be a considerable margin. So I am probably at or under the "rating" I was told while lightly loaded.

The contradiction between such a "rating" and the rating for the hubs is an interesting point.

I'll crawl under the thing again this weekend when I go and see if I can find a label. I looked from the front--time to look from the back. It is definitely quite rusty, worse than the rest of the frame underneath.

It doesn't give me much sense of up and down when I jump on it. It sure bounces like crazy when I go over bumps while towing. No swaying though. Doors pop open, stuff comes out, and even some cushions and curtains fall on the floor.

My clearance from frame to ground is only about 11 inches. The stands that came with it do not fit under, even at lowest setting (they may not be original to it). I seem to have a fist of clearance between the tire and the top of the wheel well, but the arms are definitely pointed down.

I'm pretty sure I am going to replace the axle before I take a long trip next June. I hope for a 2000 to a 2500 rating one and hope that this doesn't mean I have to move from the 13" 4-lug wheel to something bigger. I already have brakes--one of which was just replaced.

I'll check that out next spring when I take it in for a quote. Again, thank for the info.

Den

[Jared J]

You also have to subtract tongue weight.

[rabbit]

The hgt ground to frame for Escondido Burro was 14", Den. My trailer is at 13-1/2" but I added an inch in diameter to tires when I changed to 14" (1/2" additional hgt from the increase in radius axle center to ground so say it's down about an inch from original. I think yours has lost more of its throw than mine but it's a Sac City so I have no knowledge of the original clearance. Definitely look for the name plate on the back in the axle center.

jack

[kcburro]

I found the axle plate on the front end of the axle near the wheel opposite of the curb side. Can't read it though, either while under there or in picture.

I used a scrubby to clean it off. Seems like the black paint has flaked off and it is quite rusted over right where I need to see it. What I can read suggests that the middle of the second line start with "CAP" and should be followed by the numbers I am looking for. I ran this photo through various brightness and contrast levels in photoshop but still couldn't bring it out.

Is there any liquid that might minimize the rust to enable reading it?

Probably doesn't matter, since the clearance is even lower than I imagined in a practical sense. It was all I could do to get under it as it is quite low and the axle is old. Even if it is over 2000 lbs. capacity, it needs replacing. Maybe should do it sooner rather than later, especially if Dexter is leaving the scene.