Camping Trailer Project: Advice before cutting metal

Folks, looking for some advice on an impulse buy.

I bought a 6x4 3500lb trailer to use as a frame for a camping trailer. Ultimately I'd like a box compartment with a roof-top tent mounted on it, to migrate some things off the roof of the truck camper shell so I can adventure with the family while leaving the camp set up.

This is, very approximately, what I'm going for:


It has a 6'x4' internal frame dimension and a 3'6" channel draw bar. The axle is 60" to hub-face and a 5x4.5" bolt pattern. I'm expecting I can put wheel adapters and fit my stock 2nd-gen wheels on there, so I have a common spare between truck and trailer if I need it.




But - I think it's too long for what I want and too big to move around the garage. I'm considering cutting the last foot off the bed to make a 5'x4' bed and also cutting about a foot off the draw-bar to bring it to 2'6'. This would make it 8' end-to-end, so quite a bit more manageable.

That done, I plan to build a box body, with racks to accept my RTT, which is a OVS Sherpa 3-person, measuring 47" x 60" closed, so it'd be an almost perfect fit.




One consideration, though, is that it would leave the axle pretty close to the rear. Anyone know if this is an issue? Also, can anyone suggest a good guide for trailer draw-bar length?

I'd like to hear what folks thing before I do anything irreversible!

Thanks!

 

Having no weight behind the axle means all of the weight will be transferred to your tongue weight. An issue if it’ll be packed and heavy. Not an issue light or empty. I wouldn’t do it.

Shortening the distance between your truck and trailer and the overall trailer makes for very interesting backing and maneuvering as well as turning angles. I wouldn’t do that either. But go drive around with it and see how it behaves in every scenario you can get yourself into and see what observations you can make. I personally like a longer front end on a trailer for stability as well as turn radius.


If anything, chop the front corners to shed space and weight?


Measure the distance from your trailer hitch to the outside edge of your bumper and compare it to the yellow line.

 

Sub'd

 

i would probably keep the truck-to-axle distance as-is. i think it's really pretty good for a breakover angle. i'd definitely flip the axle to the other side of the spring pack though.

i'd also consider altering the rear to a 45 degree upwards taper, similar to dirt lifestyles trailer build, here's a link to his trailer build playlist:
https://www.youtube.com/watch?v=uweotzg0-FM&list=PLJ145dFO35mEpjoL0KBI7Zow7Jtk-qRwA

also note the hitch design he's using for something a little more off-road friendly.


the big thing is to figure out the gear and locations of that gear to anticipate your tongue weight. for the most part, i shoot for about 1/3 on the tongue, with the last 2/3's running on the trailer axle. but then in my trailer, i cheated heavily and plan to use the airbags to bias the load further between the two axles...

the only real thing that matters for trailers is going to be the load balance behind the rear axle and on the tongue--the rest of it is seasoning to taste-- there's enough info out there that contradicts all the other info beyond that...

 

If you really want it to track nice, measure the distance from your front to rear tire center to center and then measure back the same distance from your rear tire to the trailer tire center to center. Make it whatever length that is and get the tire width to match your truck as well and you’ll be golden.

 

Thanks for the info folks, some very informative opinions.

@BuzzardsGottaEat - fair point about not copping the length or draw-bar. After a but more thinking and a phone-call home to my Dad (who gave the same advice), I put the angle-grinder away.
The only possible length change might be if I swap out the coupler, as the current one is welded in place, so I'd have to chop about 6" to bolt a new one.

@soundman98 - yep, I'm 100% with you on the axle flip. I need the 4" to fit Taco wheels in under those mud guards.

So the current status is below - stripped down completely:


I have a few bolts to grind off, and some sharp corners to radius (around the mud guards, tail light mounts and rear end), then I think it's time to clean and paint.

The axle seems decent, so I think I'll keep it, it's a Dexter P29, rated to 3500 lb with a 61" face-to-face distance. and
I was surprised to even find grease nipples under the hub caps when I went to re-pack the bearings.



But ... it's got an arch oriented to match the over-spring perches and if I flip it I'll have to decide between running negative-camber, or getting new perches.

I see a lot of folks welding new perches on, and I have heard of some others bolting a new perch across the axle to the old perch.
I assume that all other folks who say nothing, are just flipping the axle and not worrying about it.

If I am going for a high profile tire (say 65 or 70) do I need to worry about this at all? Anyone got any experience?

@BuzzardsGottaEat on your wheelbase question: I drive a DCSB which has a 128" wheelbase, and the rear axle to ball hitch is about 48" (eyeballing with a tape measure).
So a perfect match as per your recommendation would be an 80" coupler to axle on the trailer. And measuring right now I get 81", so, yeah, I think I'll be leaving the length as-is!

 

Perfect length then, nice!

 

That's great! I hate packing bearings...

Definitely get new spring perches. The arch is there for full capacity. Same as a semi truck flat bed trailer-- it bows upwards unloaded and straightens out under rated load.

As far as bolting or welding, I would say it comes down to the forces at play. from what i can see in the pictures, it doesn't appear to be a brake compatible hub, which means that you'll never have rotational brake forces to deal with--if it has brake flanges on the axles, i'd definitely change the hubs to braking hubs for uphill/downhill trail options--and if it doesn't, but you're feeling really adventurous:

$32 BBMTA Replacement Trailer Brake Backing Plate Flange 2.27" for 3500# Axle, 4 Hole Bolt Square Bracket (2pack

https://www.amazon.com/BBMTA-Brake-Backing-Plate-2-27/dp/B0D7MX2WH6

$197 LIBRA Trailer Hub Drum Kits 5 on 4.5" B.C. w/ 10" x2-1/4 Self-Adjusting Electric Brakes for 3500 Lbs Axle

https://www.amazon.com/LIBRA-Trailer-Self-Adjusting-Electric-Brakes/dp/B0B36KF944

being that you have a welder, i would highly recommend the weld-on perches over the bolt-on, just for reduced failure points.

Amazon is going to be the cheapest, with northern tool or tractor supply more expensive but potentially more locally-immediate options.

$18 (2) Trailer axle Spring Perch/seat for 2-3/8" 3500# Round Axel Tube Mount 3.5K

https://www.amazon.com/Trailer-Spring-Perch-Round-Mount/dp/B091J42BL6

or if you want to call somewhere american that knows trailers,
https://johnsonssurplus.com/
https://johnsonssurplus.com/products/3500-spring-seat-perch-2-3-8

if you call, they'd be more than happy to set you up with a complete kit right down to the nuts and bolts needed. my dad used them for the parts to convert his camper from a 3500 pound axle(3300 pound dry weight, so just a few sleeping bags and full fridge ran the axle over weight every trip) to a 7000 pound axle, and they set him up with a kit that had everything he needed from spring mounts to lug nuts. they're not as cheap as amazon, but they know plenty, stock everything, and are semi-local to the north west indiana area.

 

Update for anyone following - axle hubs opened, cleaned, re-packed and the axle given a once-over with Rustoleum engine enamel.

By chance I came across some wheels on Craigslist that were too good of a deal to pass up: 5x Wrangler JKs with Yokohama Geolander 255/75 R17, and a spare with knobby BFGoodrich Mud-Terrains:




They are far from zero-offset, so I figure I need 9" from the trailer frame to the hub-face to afford myself 2" of clearance.
With a 49" frame and a 61" face-to-face axle, that means I'm short 3" on each side.

The hubs are 5x4.5" and the wheels are 5x5", so I'm planning a wheel adapter either way, but would a 3" wheel adapter be bonkers?
I see them on eBay for not-too-much:


I'd be a shame not to get to use the knobby tires

 

@soundman98 - great advice. I've ordered this exact pair.

I also measured the camber that it presents under no-load and by my calculation, when unloaded, I would see about 20mm extra clearance at the top of a 31" wheel/tire combo due to the positive camber.

 

Finally rolling!

When I went to size-up the wheels, it became apparent that there was no way the old fenders would fit, so they had to go:


Once chopped, it got a coat of Rustoleum Rust Reformer, followed by a few coats of Rustoleum Automotive Enamel - and the same for the old leave springs:



For anyone interested, here is a close up of the wheel spacer and "flip-kit". I went for a 3" deep 5x4.5" to 5x5" wheel adapter.
I also and found a set of axle perches that had bolts welded to them where you can put a pair of coupling-nuts to work like a machinist-jack to stop the perch from rotating.



The only downside was that the u-bolts that came with them were made of something approximating cheese, so I revived the old ones with a wire brush and shot some black Rustoleum on them, going to re-install once they dry.



Next up its to wire it for lights and get to thinking about what sort of "box" to build on top.

Anyone got any ideas? I'd like some sort of fully enclosed box with racks for a roof-top tent.

 

you do have a brake-compatible axle! i would highly recommend adding electric brakes to it, just for added control.

something i'd love to do, but don't have a use for would be to use a pickup truck service body as a base for an overland trailer. but most are larger than your current trailer platform. any one of them would easily support a roof top tent, and have ample side doors for storage. but they're also generally pretty heavy and wide as complete units... this one would need the entire top section removed, but still far cheaper than buying new steel to make the same size box layout alternatively, corrugated barn sheet metal is pretty cheap as offcuts of larger projects, but you'd still need to build the underlying structure to bolt it to. you can always check local stuff for steel tubing offcuts and second hand stuff. lots of options that are far cheaper than brand new prices, but sometimes require more prep work to get to a weldable finish.

 

A great place to get fenders is at Trailer-fenders.com. I just installed a pair and they're stout, I can easily stand on them with the fenders are only bolted at the bottom. Way better then the thin Chinese ones on Amazon. These are the narrow (er) ones designed for a 215 series tire, they also have 10" wide versions.


The trailer is a minimalist toy hauler for the motorcycle and ebike. I set it up with the same track as the tacoma and similar trailer wheel base as the truck's mostly for good handling on the hwy. No plans to take it anywhere I need 4WD so I didn't flip the axle, the added 5" of deck height would make loading motorcycles allot harder and it's frame is 20" off the ground now. The poles will support a RTT.

 

Figured I was overdue an update here - things got busy and I totally dropped the ball.
Briefly, trailer wired up, went for LED lights:

$27 Agrieyes 6" Oval LED Trailer Lights, Submersible Boat Trailer Light, with Brake, Turning Signal, Reverse Light, Backup Light, DOT Compliant

https://www.amazon.com/dp/B0C2QJH6BY?th=1
with a 7-wire loom:

$33 CheeMuii 15 FT Trailer Wiring Harness Kit Heavy Duty 7 Way Trailer Cord with 7 Pin Trailer Plug and Junction Box Kit Premium Light and Brake Wiring Wires for Trailer RV

https://www.amazon.com/dp/B0CB81BP2Z?th=1
and some small red/amber side-lights:

$9 FXC 'Purishion 10x 3/4 in' Round LED Clearence Light Front Rear Side Marker Indicators Light for Truck Car Bus Trailer Van Caravan Boat, Taillight Brake Stop Lamp (12V, Red+Amber)

https://www.amazon.com/dp/B01MEG40NI
Also wired in a tail-light to turn-signal converter so I could keep the flashing amber turn signals:

$19 Agrieyes 2-to-3-Wire Trailer Light Converter, Splice-in Trailer Wiring Converter for Tow, Tail Light Converter for RV, Dinghy, Pickup LED Compatible

https://www.amazon.com/dp/B0CZJLNCJC

 

The next step was to mock up some plywood sheeting (3/4" rough enough quality, but waterproof):



Once I had an approximate size (4 ' x 6' x 2') I build the box outside of the trailer and put some 2"x4" framing in:






and then very awkwardly tipped it into the trailer, by leaning the trailer onto it's back edge and standing the box on end. It was a tight fit, but no damage done:

 

The whole thing got a few coats of deck-painting which went on pretty well with a roller.
For anyone interested, I glued up the 2"x4" with Gorilla wood glue and then screwed it together with 2.5" wood screws, which I sunk just below the surface (you can see them if you zoom in).
Mostly it's is square, but I did have to adapt to the trailer as the frame wasn't perfectly true.

I had two pieces of angel irong hanging around so I put some Rustoleum on them and added them as cross-braces to take the weight on the roof.

Then I doubled up two layers of plywood to 1.5" thick (again glue and screws) and made a pair of doors. Note that I didn't split them evenly and left a 2" lapp on the left door to hold it behind the right:





I used standard enough gate hinges and with the plan to add a simple T-handle and some sort of rod-lock for the doors.

To hold the entire box to the trailer, I used three rows of 3 1/4-20 stainlesss carriage bolts through the floor of the box.

Not a huge amount, but it was a tight fit and the only way out was for it to slide back, so I didn't feel it needed too much.

 

Nice Progress!

 

nice!

lots more progress than i've been making... the cold hit around the same time my motivation to be outside ran out...

 

Agreed - I think this is one of the next things on the list.
I'd say I'd also try to get a hub that matches the 6x5.5 bolt pattern on the tacoma so I can use a shared spare tire.

 

I used to run 265/75-16s on the vehicle and 235/85-16 skinnies for the spare and trailer and the same height was close enough to never give me issues but the skinny spare scraped less ha. Hit whatever it’s worth, not sure what size you run on your daily.