Is this an other off road /expedition trailer brake question?

Lucky j

Hello to all who likes off road /expedition trailers.

After making a search on EP about a general tread about trailer brakes, I only found topics about either brakes issues or specific trailers and theire brake system.

My question is more for my up coming expedition / off road traile project.

I would like to know what would be the best brake system for such a trailer. It will be base on a YJ tub with Telescopic RTT rack, a awning and, 48" drawer slide, a water tank, maybe 20 gal and I want to reinstall the oem gas tank in original location. 70 litres.

So what is good or bad and for what reason. I do not have any experience with trailer brakes.

Thank you.


I guess the first question would be does the axle already have a braking system?

If so, what type of brakes are they?


My opinion based on having built a little expedition trailer, and studying and researching the heck out of this stuff.

The brakes need to attach to the axle. You will need a real trailer axle (and not a gutted vehicle axle).

I would recommend a simple leaf-spring suspension with a 3500lb trailer axle (which is plenty heavy duty for your application) with 10" electric brakes. Skip the 2000 - 2500lb axles if you're thinking trailer brakes. It is very simple to mount the axle (weld spring perches and U-bolts with backing plates), attach the brake/hub unit, and to wire up the brakes. There are just two wires going to each brake drum; a power and a ground wire. Pretty much electric brakes are the standard for expedition-type trailers. I've yet to see any other option (i.e. hydraulic or air operated brakes) on an expedition-type trailer (and that includes teardrop trailers). Parts for electric brakes are readily available.

Here's an axle example:

I ordered mine with the self-adjusting brakes. We took this set-up (axle above and parts below) from TX to northern Canada and back (including the Dempster Highway) and it all worked very well. Order a spare brake drum with bearings and seals. I carry mine inside my trailer.

If you've already got your trailer axle (with provisions for mounting a brake backing plate), you can purchase hubs with electric brake backing plates and drums to match the spindle on your axle (the hubs and brake drums are a single unit). Generally, 10" brakes start out on 3500lb axles. And with the 3500lb axles, you usually have options of bolt patterns if you're running something other than the standard 5 on 4.5".

Also remember trailer axles have a large center hub (houses the bearings), so a lot of factory alloy/aluminum rims don't have a large enough center hole for the center hub to pass through. So before purchasing rims for your trailer (or thinking you'll use factory rims) measure the wheel's center hole diameter in relation to the axle's hub diameter.

Yukon Keith and Jeep.1.jpg

Brake controller: (not the cheapest unit, but very user friendly which you will appreciate) You still want a proportional brake controller if you want to go cheaper than this proportional P3. A proportional unit makes for much smoother braking with no surprises. They cost more because they're better.

Vehicle wiring kit: I've used this kit on two separate vehicles. Take your time running and securing the wires.

Trailer wiring kit: You'll need a longer one than you think; don't cut yourself short trying to save a few dollars by purchasing a shorter one.

Junction box (makes it so much easier): Mine is tucked up between the trailer frame and tub.

I have no financial interest in etrailer; I just buy most of my trailer electrical stuff from them because they have what I need (one-stop shopping) and they're user friendly.
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Why does everyone want electric brakes on a trailer that may cross water? Ever wonder why boat trailers have surge brakes?

Electric over hydraulic. Only way to go.


New member
So I'll start by saying I'm no expert. Almost everything I've done with my trailer build was based on the information I found on this website. As mentioned above the first question is what axle do you have. I bought a surplus M116A3 at auction. It was much wider than my truck, so my first modification was to remove the axle system and surge brake and replace it with a Dexter 3500lb axle with electric brakes and parking brakes. I ordered it from a local trailer store, cost about $700. I was able to match the width of my truck (8 inches more narrow) and also the 6-lug pattern found on Toyotas. I was able to install all this myself without issues.

Like rnArmy mentioned above I then went on eTrailer and purchased a 7-wire harness kit for my vehicle, a 7-wire trailer wire connector and a mid-grade Tekonsha brake controller. eTrailer is nice because they have great customer support and installation videos for nearly everything. I wired my entire truck with my IPad right next to me with the videos.

I just tested this setup on a 5,200 mile road trip this summer to Moab and Ouray, including two days in Canyonlands on the White Rim Trail. Everything worked flawlessly. I absolutely needed the brakes on White Rim and in the mountains. Without them I doubt I would have even tried the trip.

I don't see small water crossings as a problem. I drove through two straight days of rain on the way home. That was much more concerning to me and I had no problems.Trailer.jpg


Adventurer, eh?
I do plan to go electric-over hydraulic on my truck able, but the actuator is not cheap, but that's my call on my design of my trailer and part to take full advantage of the truck axle. I did heat up my brakes on a long and steep hill, where I also ran hot going up because of how steep and slow I was going. In an off-road scenario you're going slow where it's not much of a problem, but on public roads, you don't want to slow down traffic behind you to a crawl either. For the most part, the truck's brakes have been absolutely fine except for that one circumstance, which means I'm not taking it on a trip to BC like that.

Question is, is it cheaper to keep the axle, tires and rims and get a EoH actuator, or is it worth your while to get a new axle with spacers to match the vehicle's track width and bolt pattern? I read that electric brakes like to work as more of an on-off, while EoH should be progressive, and MUCH stronger.

If you don't want to go EoH, you can go with surge brakes. I don't have experience of them outside of the army, so all I know is they they're a pain when reversing on a surface with resistance, causing the brakes to lock up when you're trying to push it backwards


With a electrical brake proportional unit (like the P3) it is not "on-off"; instead you can adjust how much max power goes to the brakes, and it will gradually increase the amount of braking effort based on how fast you're trying to stop. If it was "on-off", you'd always be locking up your trailer's brakes.


As a previous poster said, a 3500lb trailer axle with brakes is easy to swap into just about any expedition trailer.

And I've drug my electric brake equipped M416 through many water crossings and have never had an issue, even in 2' deep water.


It was stated that boat trailers have surge brakes because of the water issue.

Just to be specific, it's why boat trailers have hydraulic brakes. The fact that those hydraulic brakes are actuated via a surge system is due to cost, it's cheaper and there are no compatibility issues to crimp sales.

Electric over hydraulic is more expensive than straight electric, and requires a controller in the vehicle that can "talk" with the electric to hydraulic unit (it's different than talking to straight electric brakes).

But hydraulic brakes are the most reliable and without an air unit to drive them, the other option is an electric over hydraulic unit. If you are starting with an axle that has hydraulic brakes already it's not as expensive as it first appears, as you will not have to swap out the hydraulic brakes for electric brakes.

It's all up to you, but I would argue that electric over hydraulic for a trailer that may see water crossings is the only sure way to have brakes and not risk water problems.

As one poster mentioned, he's gotten away with. But some folks run their rigs way over gross and get away with it too. Until they don't.
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If you were concerned about water shorting out the electric brakes, you could always put a HD switch in-line with the power wire going to the brakes (would be simple enough to do). Then just switch-off the power going to the electric trailer brakes when doing a water crossing, and turn them back on once on dry ground.


This puzzles me.
If by "servo" is meant the electromagnet within the brake assembly. A short circuit would render the brake nonfunctional.
Without electric power, "Locked up" would be a mechanical problem.
Yeah I didn't get that statement either...


On electric brakes you are required to have a breakaway actuator and if it gets we the brakes will try to lock up. To disconnect you have to remove the power wire from the towing vehicle and disconnect the battery on the trailer.

Surge brakes are actually a superior system.

Sent from my iPhone using Tapatalk Pro



Thats a simple remedy of not using electro-crap trailer parts.
Sadly the Trailers Business is awash with that kind of crap & most folks dont understand the difference.

Fwiw, Just getting wet I dont think is so bad, Water being not a good conductor.
I expect its corrosion what follows cause conductivity & thus braking.
Water is horrible at conducting electricity. The ionized metals contained therein, however, are very good at it.

Lucky j

Was not able to come back to my own tread until today, and many answers already.

Thank you very much guys.

I should have mention that the frame will be built from scratch to fit the tub, the axle will be a a length cut to spec with the right bolt patern that in my case will be 5 - 5 1/2", so no problemes with wheel center. Axle with 3500 lbs bearing and spindle and I will try to come bye with a soft suspension to take care of the washboard type of back road we have in the north east of the continent. And since it will be a dedicated travel trailer, I should be able to keep my load consistent from trip to trip.

Oh yeah, forgot, I want to have some kind of parking brake to if possible.

And I do not want to go with the jeep axle cause I am sure that the trailer axle will be lighter and have better clearance.

Now I will go back and read all your responses.

Thank you again.
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