5x114.3 to 5x120 wheel adapter. Yay or nay?

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So I bought this 1991 cal-trans trailer. Well built heavy duty trailer on Leaf springs. My original plan for a trailer was to get it on some bigger offroad wheels. But this thing has small fender flares and the axle set up has hand brakes. They have new axles online that are 5x120 but then I lose my hand brakes. Going with bigger wheels I'd have to cut the fenders off. Which is no biggy. Main question is. Are adapters safe? I want to use my stock FJ cruiser wheels on my trailer if possible. Hers a ghetto quick rack I built so that I could use it for the few trips we had booked. I made it so I can raise the tent at destination and lower for less drag while driving. First time using the trailer and rtt I got 40 mph winds. Almost pooped myself.
 

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smritte

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If they bolt on the existing studs and are not much more than an inch thick, you will be fine. I'm assuming the trailer isn't 5k or more in weight.
Why cant you get a hub in the correct bolt pattern? Axles have standard spindle sizes. I find it odd they would only offer one bolt pattern. I got a new Dexter axle for my last trailer project with brakes and if I remember it was under $400 in whatever pattern I wanted.
 
If they bolt on the existing studs and are not much more than an inch thick, you will be fine. I'm assuming the trailer isn't 5k or more in weight.
Why cant you get a hub in the correct bolt pattern? Axles have standard spindle sizes. I find it odd they would only offer one bolt pattern. I got a new Dexter axle for my last trailer project with brakes and if I remember it was under $400 in whatever pattern I wanted.
I haven't done much research. I don't understand this stuff enough to know where to start. But that site was recommended to me by a member here. I figured if I can get away with adapters I can use my existing wheels I took off my FJ. And just stick with it. Im going to flip my axle first to see if I can get the clearance. The axle I have on the trailer is not your usual round shaft type. Not sure what it's called. But it's rectangular. And the center of hub is offset from the main axle.
 

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Be careful flipping the axle, some axles are bowed for camber. If the axle is bowed and you flip it, you will chew up bearings. If your axle tube is offset down a few inch's, its normally called a drop axle. This is done to lower the weight. If you can flip it, you may have to weld on new spring mounts and if the U-Bolts are a bit old make sure to replace them and torque them.
Replacing axles is very common. Pop by a local trailer shop and talk to them. If you were a bit closer to me, I would send you to the one I use. The one by me has an axle work sheet. You fill in how long, round or square tube, with or without brakes and what lug pattern.
 
Be careful flipping the axle, some axles are bowed for camber. If the axle is bowed and you flip it, you will chew up bearings. If your axle tube is offset down a few inch's, its normally called a drop axle. This is done to lower the weight. If you can flip it, you may have to weld on new spring mounts and if the U-Bolts are a bit old make sure to replace them and torque them.
Replacing axles is very common. Pop by a local trailer shop and talk to them. If you were a bit closer to me, I would send you to the one I use. The one by me has an axle work sheet. You fill in how long, round or square tube, with or without brakes and what lug pattern.
Thank you. I'll see if I can find a trailer shop. Only worry is I know so little about this stuff I don't want to get hustles. I'll post a picture of my axle tomorrow when it's bright out.
 

smritte

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That would be considered a drop axle. I don't see any arch to it so you should be able to flip it. Before you start, lift one of the springs and see if there is a peg/dowel/pin sitting in a hole in the axle. This indexes the spring. These come two ways. Either a bolt, holding the spring pack together or molded into the lower spring. Its purpose is to center the spring and keep it from sliding out. When you flip the axle you will have to drill a hole in the same spot.
if you bought an axle you would either specify where you wanted the springs to sit and they would supply you with mounts (perch's) either for you to weld or welded in the place of your choosing. The spring perch already would have the indexing hole.

Make sure you replace the u-bolts and nuts. measure the length and width. The width is the important measurement and you may have to shorten them some. When you do this, you can have the u-bolts facing up if you like. Keeps rocks from hitting the ends and bending them.

Another mod I would strongly suggest is mounting shocks under there. If you saw how bad my trailer bounced on dirt roads before I installed them, it would scare you.
To keep the bouncing down, I would drop the tire pressure to about 12 on dirt roads then air them back on pavement.
 

m1101tenttrailer

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im also interested in the wheel adapter idea. i have this humvee trailer with 8x6.5 lug pattern. i found some wheel adapters online that can changes it to a 6x5.5 to match my tow vehicle. the trailer is less than 2500 lbs. is it safe for overloading?
 
im also interested in the wheel adapter idea. i have this humvee trailer with 8x6.5 lug pattern. i found some wheel adapters online that can changes it to a 6x5.5 to match my tow vehicle. the trailer is less than 2500 lbs. is it safe for overloading?
I just reached out dinoot . A new trailer with 6 x 5.5 to the length and offset you need will be just over 200 including shipping. At least that's shipped to me in california. I think they're based in Oregon. The owner is very fast with email responses and is very helpful since I am a total noob .
 

m1101tenttrailer

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I just reached out dinoot . A new trailer with 6 x 5.5 to the length and offset you need will be just over 200 including shipping. At least that's shipped to me in california. I think they're based in Oregon. The owner is very fast with email responses and is very helpful since I am a total noob .
Thanks man. Can you give me a point of contact?
 

smritte

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im also interested in the wheel adapter idea. i have this humvee trailer with 8x6.5 lug pattern. i found some wheel adapters online that can changes it to a 6x5.5 to match my tow vehicle. the trailer is less than 2500 lbs. is it safe for overloading?
Most likely yes. Make sure their no thicker than about an inch. Properly torque everything. If you have a link, that would be nice.

Regards,
Scott Chaney, Owner
Compact Camping Concepts
Salem, OR
This guy is cool as hell. He has a small off-road trailer forum. When I built mine a long time ago, I got some great ideas from there.
 

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DO NOT FLIP A DROP AXLE!!!

The torque from the leverage the hub has on the leafs will break the leaf springs. Your best bet is to purchase a 3500lb straight axle with the correct bolt pattern hubs or ones that you can get SINGLE PIECE adapters for. Custom made straight axle will run you about $400 shipped with hubs/brakes. Any trailer supply shop near you should be able to order you an axle from Dexter(or equivalent mfg). You will need to provide them with 2 measurements; Center to center of your leaf springs and hub face to hub face distance.

You can also order a Timbren Axleless Suspension kit and remove the axle and leaf springs completely. You can just drill/bolt on the new assemblies to your frame rails and move on with more ground clearance and a better ride. If your trailer weights under 1500lbs I would use the 2200lb TONNE system
 
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smritte

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The torque from the leverage the hub has on the leafs will break the leaf springs
I'm sorry but I'm going to disagree with this statement. If your going to have an issue, its going to be with the hub assembly "if" there is any camber built in. Leaf spring's flex very well and the only way your going to stress them is through lateral force. Putting the springs into a slight sideways twist will most certainly trash the bushings.

Unless I'm missing something here. There isn't going to be any outside of the normal movement. Axle manufactures add in some camber to help stabilize the load while driving. It reduces the "side to side" movement common in trailers. This axle did not appear to have any. If it did have any, he will chew up bearings. This is something I've seen happen a bunch over the years.
It was also suggested he just buy an axle considering if he shopped, springs and axles normally run under $500 for everything.
 

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The concern I would have with flipping an axle would be alignment related, which would be fixed when you weld on new spring perches. Other thing to worry about would be if the axle has any bend in it, if it does you wont want to flip it (many trailer axles have a small amount of bend). I have flipped and moved around axles on trailers before and never had issues, you just need to be careful and take your time.
As far as wheel spacers go, I wouldnt.
Honestly trailer axles in general are cheap, 9 times out of 10 youre money and time ahead to just swing in a new axle that is exactly what you want and sell the old one on craigslist. Only reason I have messed with trailer axles in the past is when they have been on odd ball stuff and the parts houses that carry axles are closed, and I needed the trailer before the correct axle would arrive after being ordered.
 
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Anchor Mtn

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I'm sorry but I'm going to disagree with this statement. If your going to have an issue, its going to be with the hub assembly "if" there is any camber built in. Leaf spring's flex very well and the only way your going to stress them is through lateral force. Putting the springs into a slight sideways twist will most certainly trash the bushings.

Unless I'm missing something here. There isn't going to be any outside of the normal movement. Axle manufactures add in some camber to help stabilize the load while driving. It reduces the "side to side" movement common in trailers. This axle did not appear to have any. If it did have any, he will chew up bearings. This is something I've seen happen a bunch over the years.
It was also suggested he just buy an axle considering if he shopped, springs and axles normally run under $500 for everything.

They are called DROP axles and not DROP/LIFT axles for a very good reason and it has nothing to do with the camber built into the beam. Even a spring over(leafs on top of the axles vs standard leafs UNDER the axle) will shorten the lifespan of a trailer leaf spring.... and adding ~5" of extra leverage will only exaggerate the problem. Ive seen it over and over in my 10+ years building custom offroad trailers. Theres a reason I dont offer drop axles OR trailer springs on any of my builds....they just dont last.

Quick home demonstration:

Take your hand and make a fist(axle), and lay your elbow(leaf spring) flat on the table. "Drive" your fist across the table into a small object and see how the force effects your arm. There is a small bind and then you push your fist over the object.
Now take your fist and put it straight down on the table(your elbow 90deg to the table) and "drive" it across the table to the same object. Your elbow now sees a rotational force it didnt see before.
 
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smritte

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Then we will agree to disagree. I wont compare resume's but I would be willing to bet in my several decades of fabricating and engineering our experience is at least similar. I too have built off-road trailers and have so for way longer than a decade. My current build has been over the Rubicon, Dusy and seen a ton off road miles as well as ones I have built for others..

Your example I find interesting considering the force your applying isn't going to happen unless you strike the wheel with a considerable force sideways. Even then, if you broke a spring, that would be the least of your problems. I'm not sure how an axle that is not flexing is going to amplify shock like you describe. If anything the hub assembly is going to bend. I'm sure you have seen portal axles. Why do they work? Look at drop spindles people run on vehicles. And yes, I have seen portals with leafs.

In the 90's when we all had leafs on our rock crawlers, we would bend and twist all day long. It wasn't uncommon to slam sideways into a rock similar to what you describe. While we occasionally bent springs, it wasn't common to break them. I have seen vehicles flip sideways off a rock and land on their side hard enough to bend the cage and the axle's. The leafs were fine. 40" tires will have way more leverage then were discussing.

I don't want to get into a "theoretical" debate over something on the web and will not be replying again to this post. If you read through the post, the OP went another direction. I will agree that flipping a drop axle is not a best practice and I also suggested he get a proper axle like you also suggested.
 

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Are adapters safe?
yes.... if follow the directions precisely
and if you are not running fully loaded.

if a spacer moves the wheel center line outboard, you have dramatically changed the stress on the spindle
but if your 1.5" spacer is offset by a rim with 1.5" more back space, the leverage, dynamics have not changed.
 
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Billiebob

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Leaf spring's flex very well and the only way your going to stress them is through lateral force
not when you flip a drop axle. you go from a hub in line with the spring pack center to a hub several inches below the the spring pack center. that extra leverage will break leaf springs.