Replacing trailer axle... what are the considerations?

jimmwaller

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Hello all,
I think it's time for me to replace my trailer axles. My bearings/hubs are pretty rusted and now that both my tires have gone flat, this might be the motivation I need to replace the whole axle assembly.
Just to make sure I'm doing things right... what are the considerations that I need to keep in mind when replacing an axle? Things like fit, weight, etc. So far, I feel like I have to make sure that:
1) the length is correct. This one is pretty self-explanatory, I'll just match what I have now.
2) the "leaf spring center" is correct. However, my trailer doesn't have springs. The axle just basically bolts to a bar hanging off the bottom of my trailer frame. Is there any way I could add leaf springs?
3) The weight is correct. I have an old aluminum starcraft islander, so I figure that a #3500 should be plenty, or is that overkill? Or should I get a beefier one?
4) Do I need to consider the size/shape of the axle? My current axle is square, and I'm planning to stick with square. But do I need to make sure the dimensions of the tubing are exactly the same, or does that not matter as much as long as the U bolts fit?
5) I don't really care what hubs it has on there. I'm planning to replace the wheels/tires anyways, so I'll just make sure I get wheels that fit.
6) I use my boat in a saltwater bay, is there anything I can do with the axle purchase to ensure that it lasts? What's the best material for saltwater?
7) anything else I'm missing that I should be thinking of when buying/installing a new axle? I feel like it's really just a matter of unbolting the old and rebolting the new, is that the right way to think about it?

Thanks so much!!
 

JimS123

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Rust and flat tires are more of an indication of poor maintenance. If the trailer combo was correct in the beginning, then why is what doesn't need fixing.
Tire / wheel combos are easily obtained on the internet. Actually, going this route is usually cheaper than buying tires and mounting them on old rusted wheels.
Bearings and hubs are also a simple commodity. They can also be had fully assembled with little knowledge need to install them.
Pull apart what you have, clean the spindles with emory cloth and steel wool and simply reassemble.
If the axle is in that bad a shape, trying to remove the existing bolts will probably be more effort than what I suggested.
 

jimmwaller

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@JimS123 ok, I think I see your point. If I'm understanding correctly, you are suggesting that I just pull the hubs off the existing axle and install new hubs?

That's totally fair, I'm not sure why I didn't think of that. So then, I'll ask my same question but about hubs: What considerations do I need to keep in mind as far as hubs? I guess I need to make sure I get the right spindle diameter, but other than that... any hubs should work, right? Is there a "best" bolt pattern that will tend to have a wider availability of parts?

I'm also interpreting your message to imply that it's not a problem that my trailer doesn't have leaf springs. I should mention that this trailer looks a little bit... janky. I can't imagine a trailer being built without springs, and this trailer looks like a good candidate for the Previous Owner to have just bolted the axle in place when there was originally springs. But should I not worry about this too much? Or is it worth putting springs in?

Thanks!
 

XS POWER

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Post some photos of your trailer. Only ones I have seen with no springs are Jinkers.
 

redneck joe

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I had many questions as well

 

XS POWER

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Yea well that would explain the lack of leaf springs. Photos suck take some of your considerations.
 

JimS123

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What considerations do I need to keep in mind as far as hubs?

Previous Owner to have just bolted the axle in place when there was originally springs. But should I not worry about this too much? Or is it worth putting springs in?
If it were me the first think I would do is tear them down and see what we have to work with. Surface rust? Internal rust? Surely, the bearings need to be replaced, but maybe a simple race replacement is all that's needed. If the whole hub needs to be changed, just buy in like kind.

Axles need either leaf springs, coil springs or a torsion bar. Your picture doesn't show the axle so I can't tell what you have.

If its simply an axle bolted to the frame, my guess is you couldn't drive down the street without great pain.
 

jimmwaller

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ah, so... turns out I was very wrong about the leaf springs. They're there, just VERY rusted to the point that I couldn't see them without a flashlight. so those will get replaced.

At this point, my strategy is to jack the trailer up and take off one wheel, pull the hubs/etc and get everything down to the spindle. Then I'll get some photos for you folks and get your recommendations on whether or not I'll need new axles or whether I should just use the axles I have.

The good news is that it looks like there's a TON of rust under there, but the axle looks like it's in good shape still. The rust seems to be limited to the wheels, hubs, U bolts, and leaf springs... the actual axle looks decent. I hope this ends up being the case as I pull everything apart.

Thanks for all of the help so far!
 

Chris1956

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If you know the brand of the trailer, you can look at the large trailer places like etrailer or eastern marine. Their websites have OEM replacements, that may tell you exactly what you had new. Armed with that knowledge, you can pick and choose what you want to replace. It does look like you have torsion bar axles, though.

Clearly you need to match axle length, style and capacity, along with leaf spring length and capacity and tire size and capacity. These can be had from multiple sources.

Check the axle carefully. They get water inside them, it sits and rusts it out from the inside. If in doubt, replace them, as they are relatively inexpensive, compared to supports, bolts, rollers and other accessories. New axles often also come with new hubs and bearings installed. Having them break on the highway is real bad....
 
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jimmwaller

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@Chris1956 Thanks. I have no idea what brand it is, I can't find a plate or vin or anything on it. Is there some place where this information would typically be, or some hidden place where manufacturers are required to stamp info as a backup or something?
Thanks!
 

jimmwaller

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Found an empty plate on the inside of a crossbar... looks like it's a Calkins trailer?


IMG_5280.JPG

Also took some measurements of the axles & etc. My understanding is that if I buy a new axle and leaf springs, and the axle has the hub and everything on it, I can just bolt in the leaf springs, bolt the axle to the springs, and then I'm basically good to add wheels and roll? Or am I missing something critical?

Thanks!
 

JimS123

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Found an empty plate on the inside of a crossbar... looks like it's a Calkins trailer?
My understanding is that if I buy a new axle and leaf springs, and the axle has the hub and everything on it, I can just bolt in the leaf springs, bolt the axle to the springs, and then I'm basically good to add wheels and roll? Or am I missing something critical?

Thanks!
That's sounds just about right. But since you also have the serial number from your registration papers, why not contact Calkins and see what they have to say.
Regardless, before you replace anything, with all the rust you have described, look at the trailer frame and see if its worth restoring.
 

jimmwaller

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@JimS123 I don't have any kind of serial number, unfortunately... trailer did not come with any kind of paperwork or anything.

But on the trailer, it's galvanized and the trailer BODY looks pretty good. There's a little bit of surface rust but it seems like the body is in good shape. The things that have rusted are the hubs, leaf springs, etc. I included a photo that shows the rusted hubs but also the trailer body, which I think looks like it's in decent condition but would be happy to know if others disagree.

But, I'm having a bit of a tough time finding a replacement axle. My axle is a square, 2x3 axle, with 75" spring centers, with a drop. The measurement between the brake flanges is about 81" and it's about 84.5" from hub face to hub face.

I'm seeing a couple of 2x3 drop axles, but nothing with 75" springs. Which dimensions can I play around with here? Could I switch from a drop to a non-drop-axle? Or use a different brake plate measurement, or hub face measurement?

Thanks!

EDIT: I should add, when I say a drop axle, I don't mean "drop center" in that there's a bend in the axle. I mean that the axle is off center from the wheel center and has a plate to raise the spindle up, like so: https://www.easternmarine.com/8775-2-x-3-square-drop-galvanized-trailer-axle-6000-lb
 

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JimS123

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Galvanized with surface rust. No problem. The issue is how much rust is inside. Was it hot dipped or not? I dunno. The pictures make me worried, not to mention no paperwork or SN. Replacing the axle means taking off bolts. You'll probably need a torch.

All time and expense. If it were me I'd buy a new trailer. When the running gear looks that bad I would not drive it on the highway with my beloved boat on top.

But that's just me. I'm retired and don't have the time to worry about having my trailer crash behind me. That happened to me in my youth and it ain't gonna happen again.
 

jimmwaller

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@JimS123 that makes sense! Is there any way to find out whether it was hot dipped and/or how much rust is on the inside?
This boat is a 22-footer, so used trailers are few and far between, and new trailers are thousands of dollars. If my trailer body is in decent shape, and I can replace the axles, hubs, springs, and wheels for a few hundred dollars and get a trailer that I can trust and is in good shape, I'd rather just replace the parts that need replacing. But I hear you—if the inside of the trailer is unknown, maybe it's better to buy a new one. But is there a way to determine the structural integrity of this trailer at all?
Thanks!
 

dingbat

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@JimS123 that makes sense! Is there any way to find out whether it was hot dipped and/or how much rust is on the inside?
That axle is hot dipped. Can tell by the pitting

Your looking for “rust” stains coming through the coating. Can look pretty bad cosmetically yet still be sound.,

Grab a hammer and tap/bang the bottom of the axle across the width. Particularly in the center. Should respond with a solid ring to it. Pretty easy to tell if it needs replaced
 

jimmwaller

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@dingbat thanks. Just to make sure I'm understanding, hot dipped means that it's probably pretty rust resistant, correct? So you're saying that if I tap on it pretty thoroughly and it sounds like metal, it's probably in good shape? What will it sound like if it's no good, will it just sound dull or will the hammer, like, punch through or something?

Does that go for the rest of the trailer, as well, or just the axle?

Thanks!
 

dingbat

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@dingbat thanks. Just to make sure I'm understanding, hot dipped means that it's probably pretty rust resistant, correct?
Hot dip is a process through which an extrusion (axle) is dipped in a pot of molten zinc and let to cool and dry.

The superior corrosion resistance comes from having the cross section completely coated, inside and out, leaving no bare metal exposed to rust.

Over time the zinc coating gets eaten away and moistures comes in contact with the under laying steel starting to rust


So you're saying that if I tap on it pretty thoroughly and it sounds like metal, it's probably in good shape?
Yes
will it just sound dull or will the hammer, like, punch through or something?
Both
Does that go for the rest of the trailer, as well, or just the axle?
Yes
 
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