Independent Brake Wire Feed Upgrade

[JohnB]

Hi Fellow Campers

I have had a number of folks ask about my brake wiring upgrade, what is it and why. So here is Pict–O–Gram on the topic.

First of all what is this all about. It deals with the ability to get full braking electrical power to the wheels all the time. If you look across many brands, the brake wiring is worse then others. Sunline is better then most but still have some inherent issues as the camper ages over time.

This deals with the wiring from the 7 wire plug all the way to the actual magnet on the brake plate. On my camper, Sunline did at least use no. 10 awg wire as the main feeder. Some brands use 14 or 12 awg. These smaller gage wires have a larger voltage drop to them. However the biggest area of issues is at the wheels themselves and the connection from the wheels to the main feed line.

Here let me show you. As you can barely see in this pic there are wires that jump down to each wheel brake plate.


And this pic you can see the main blue feed line and how the power jumps to the rear axle. The front axle is the same.


A few problems with this setup over time. Corrosion and age is the problem. First there is a double stand wire that runs thru the axle tube. It joins the 2 sides. That wire becomes brittle over time. It also rubs the wire insulation against the inside of the axle tube. When I took my old axles off I pulled out a section of the wire and flexed it. It was hard and brittle. As I flex it once, it cracked completely 360 deg around the wire. I could then see the copper thru the crack. H’mm not good. This was a 5 year old camper at this point. If the wear gets advanced enough it can actually short out the brakes. Mine was not yet at this stage.

The next area is corrosion. My son had his Colman PU over here this spring and we where working on the brakes. I looked under the camper and could not believe what I saw. I have heard of this but now I’m seeing it. Skotch lock quick connector out in the open used on brake connections. See pic. These connections are exposed to the weather and are really not a great wire connection when you want the lowest resistance you can get on a brake circuit. While this may have squeaked by when new, time and corrosion will do these in IMHO.


They make these skotch locks with a gell in them, (most likely dielectric grease) but still I’m not a fan of them in a brake circuit.


On mine, Sunline took a different approach. Better at least. They used crimp wire nuts then filled them with a dab of silicone. You can see the grommet that shields the wire as it goes into the axle tube is already cracked and split and a piece missing. Sooner or later that areas will wear thru the insulation and into the wire.



Here it the single side of the axle. Just a 2 wire splice not a 3 wire merge.


Then to join the axle wires to the main feed they did something a little strange. They torched a hole in the frame, put a plastic grommet in and then joined the wires on the tire side of the frame.




I really do not know why they did this. The wet from the wheels flies into those connections and the ground uses a copper lug with a steel set screw all exposed. The steel set screw rusts bad over time. Mine are rusted heavy. Rust on a ground is not good as the electrical connection thru it can at times become insulation instead of conducting and things stop working.

When I replaced my axles I had a choice. Hook these up the same way or upgrade. So I choose to upgrade.

I did not use the brand new wire inside the axle tubes. After seeing how brittle my old one was, the reports I have heard of with shorts in the tube I can see this for sure occurring. I also changed the wire size. I went no. 10 all the way. Some go a no. 10 main feed then jump to no. 12 to each wheel. Now 12 is better then the no. 14 that was there but I took the heavy route. I also changed the hook up method.

On this setup


If that joint in the red wire nut is corroded or caught in something and breaks loose it stops 2 brakes from working. So I went direct to each wheel independent and then up to a common junction box to join.

See here. First I connect at the wheel. In my case I soldered the wires together, used heat shrink tubing then followed by 3M 33 premium electrical tape. The single conductor stranded wire is slid in a piece of plastic tubing. The tubing is to help protect the wire from sun damage and the elements. This connection has very little resistance, will not break loose and has increased corrosion protection. Plus it is rigidly held in place.


The wire hoses go to each wheel independent. The tubes are on the back side of the axles on purpose so they do not catch something when going over what ever. The axle takes the hit first.


Then up to a high up junction box. A stainless clamp holds the hose from pulling out. The hose is a press in drilled fit in the fiberglass box. Its location is dry even in the hardest of rains. I jumped from the axle to the box in the middle of the axle. You have to make the jump somewhere, this seemed to be the better area.




Inside the box I again soldered the connections, shrink tube and taped. Then the cover went on.



Some who have done this independent brake magnet feed upgrade use dual wire. 2 wires in a case. I used single strand and tubing. I had the tubing laying around and had a cheaper source to the no 10 copper stranded single wire so went that route. See here for 2 strand in case you are looking http://www.etrailer.com/p-10-2-1.htm

I now know I have greatly reduced my corrosion risk, the axle rubbing issue and voltage loose getting to the brake coils. Since I had the option to hook up the old way or the upgraded way, I went the upgrade.

I unfortunately did not do voltage drops measurements on the old system then on the new system. Missed that. But the corrosion and brittle wire was enough to convince me to upgrade. I do know my TT brakes are now a lot more power full then they use to be. My rear brakes on the F350 use to dust heavily before only when towing. Now they don’t . Why, the truck is not doing so much of the stopping any more.

I’m not saying everyone has to run out and do this upgrade, but if you are having issues with stopping power a voltage check at the wheel can help uncover a corrosion or voltage drop issue. And if you find yourself in that case, this is an option to upgrade. I was not the first to invent this concept, others have done it before mel. I just borrowed there idea and applied it in my situation.

Hope this helps someone in the future.

John

[Steve Collins]

Originally Posted by JohnB

In my case I soldered the wires together, used heat shrink tubing then followed by 3M 33 premium electrical tape.

Amen!

[frank]

I did this upgrade as well, and can attest the independant feed does make a very noticable difference in braking performance.

Prior to the upgrade, I had "weak" brakes and an occasional overload showing on the P3. Losing trailer brakes on a road like 76 thru Philtydelphia is no picnic! I pulled wheels and drums and went over every inch of wire that I could several times trying to find the fault and everything looked good. The only thing I couldn't easily see was the wiring in the axle tube. I decided if I was pulling that out I was doing the independant upgrade.

When I yanked the wires out of the axle tubes, I found that the insulation on one of the wires had worn through in the middle of the tube. Apparently the loose wire in there bouncing up and down took its toll over time. I would have expected it to wear through at the ends where it feeds through the bushings but that was not the case.

Anyway, I used what I had on hand and made four harnesses out of 14 AWG single conductor taped together and wrapped in plastic loom. Ran them on the outsides of the tube as John did and made a single master connection to the stock 10AWG feeder in front of the axles.

End result is no more faults on the controller and needing to back the P3 down 2-3 volts to get the braking level right. Saying the difference is night and day is an understatement.

Big thanks to John for bringing up this concept a few months back when he was doing some other work on his TT.

- Frank

[JohnB]

Frank

Extra wire inside the axle tube, yes there is a quantity stuffed in there. See here on one of my new ones the excess hanging out one end.



And that was not all of it. I suspect there is yet another 6 inches on that end and equal on the other. Assuming they put in extra so you can always pull out some more if you have to cut some off to splice on a new coil.

But, as we both have found, that wire, even inside the tube turns brittle. The insulation must not be a great outdoor value…. With all the extra wire zig zaged stuff in there, you seem to have proved it eats away at the insulation and eventually starts a short.

I was almost tempted to fuse each coil feed. With lie a 15 amp fuse. That way if one coil has a hard dead short it does not trip the 30 amp fuse in the truck and then you have no brakes. Something that is very able to happen if a coil wire get wound up wrong in the brake area. However I did not research the fuse holder to not have a voltage drop for the added connection. In my case I can still add them if I choose to.

It’s almost like you want a self resetting circuit breaker and not a fuse. I’ll ponder this one some more. Having a heavy truck helps if your TT brakes go out as it has to stop both then. Using a smaller TV in relation to the TT make the challenge even more complex. Which is why I now put a twisty tie around the 7 wire plug door cap to keep the plug from falling out. I had the 7 wire fall out 3 times on this F350, all in the camp ground going slow, was lucky. From then on, it’s tied shut and will have to yank the receptacle and all to come out.

John

[Sunline Fan]

Originally Posted by JohnB

Which is why I now put a twisty tie around the 7 wire plug door cap to keep the plug from falling out. I had the 7 wire fall out 3 times on this F350, all in the camp ground going slow, was lucky. From then on, it’s tied shut and will have to yank the receptacle and all to come out.

John,

While I've never had a problem with the Excursion plugs, the F-450 plug is very loose. And it's straight on too, whereas the Excursion plug is on an angle and the cord plug has to turn to go into it and is under a bit of constant tension, not to mention the design of the door/catch is much better/stronger.

When we had the F-450 out towing, our friends behind us said that as I used the turn signal, sometimes it would work, sometimes it wouldn't. They could see my mirror to know I had it on the whole time, not to mention I am one who doesn't do just one flash. The occasional operation could have had something to do with the rain, though I hope that wasn't the case.

Here is my solution. It's the most stylish one I could come up with.

Broccoli is good...



Jon

[kanyonkitty]

I have never had this issue with my '05 F-350, but ya never know when it could start. You got me wondering about using one of these:

http://cableorganizer.com/wire-wrap/...o?=recommended

I use them now for lots of stuff, and thought, hum something I already have maybe I can use it for the plug too.


BUT, Jons' "Broccoli Band" is very stylish, price is very reasonable, and as long as you keep eating broccoli, you have a never ending supply


Kitty

[frank]

Originally Posted by JohnB

I was almost tempted to fuse each coil feed. With lie a 15 amp fuse. That way if one coil has a hard dead short it does not trip the 30 amp fuse in the truck and then you have no brakes. Something that is very able to happen if a coil wire get wound up wrong in the brake area. However I did not research the fuse holder to not have a voltage drop for the added connection. In my case I can still add them if I choose to.

I thought about this also when I did the re-wiring. The reason I didn't go for it then was the P3 and how touchy the protection circuitry is. I'm not sure I'd trip a circuit breaker or pop a fuse before it dropped out. One of these days I need to give Tekonsha a call and see if I can get any specs on what it will take before kicking out with "overload."

Originally Posted by JohnB

Which is why I now put a twisty tie around the 7 wire plug door cap to keep the plug from falling out. I had the 7 wire fall out 3 times on this F350, all in the camp ground going slow, was lucky. From then on, it’s tied shut and will have to yank the receptacle and all to come out.

John

Wow, I have the exact opposite problem with the GMC. The 7 pin is so darn tight it almost takes two hands to get that thing out!

- Frank

[MACK C-85]

My Dodge has a clip on the spring loaded cover that clicks down over the back of the plug and holds it in. I've never had a problem with the plug coming out. Althought I will say, it doesn't take two hands, but it's a pretty snug fit.

Mack

[Sunline Fan]

Originally Posted by MACK C-85

My Dodge has a clip on the spring loaded cover that clicks down over the back of the plug and holds it in. I've never had a problem with the plug coming out. Althought I will say, it doesn't take two hands, but it's a pretty snug fit.

Mack

The Ford plugs have a clip too but the spring on the SD plugs aren't so strong.

Jon

[MACK C-85]

MACK C-85 wrote:
My Dodge has a clip on the spring loaded cover that clicks down over the back of the plug and holds it in. I've never had a problem with the plug coming out. Althought I will say, it doesn't take two hands, but it's a pretty snug fit.

Mack


The Ford plugs have a clip too but the spring on the SD plugs aren't so strong.

Jon

That's the fun part of hooking mine up, trying to hold up the cap against the strong spring with one hand while trying to push the fairly tight plug in with the other.

[wagonman76]

Nice work.

Had I kept the drum setup on my trailer, I would have done something similar. The wiring is just too chintzy, and better wiring is peanuts compared to an accident due to faulty brakes.

I only question one thing, you said you used single strand wire. Won't that end up fatiguing more easily over time between the j-box and axle, with the movement of the axle?

When I was less experienced, I used to love those scotchlock connectors, now I can't stand them. I used them to attach my trailer connector. After one winter the wires turned green and fell apart. At the same time I used them to attach my brake controller, inside the vehicle. No corrosion, but the metal clip eventually loosened up and I kept losing the trailer brakes. Anymore I solder everything, and heat shrink or at least tape it really good.

My 7-wire plug has never fallen out but I don't like how loose it is. On my old vehicle and trailer, I used a 9-wire plug and connector. It's the same size and shape as the 7-wire but it uses straight and tight pins instead of wobbly blades. The original reason for using it was I wanted a wiring path for the 3rd brake light I added. But I like the security of the 9-wire, and the connection quality has gotta be a lot better. I've been thinking about putting a 9-wire on the Sunline. I already have cords I made to go from 9 to 4/7 and 4/7 to 9.

[JohnB]

Originally Posted by wagonman76

I only question one thing, you said you used single strand wire. Won't that end up fatiguing more easily over time between the j-box and axle, with the movement of the axle?

Hi Wagon

H'mm I'll have to go back and reread how I wrote the words. You used "Single strand" wire.

That was not what I meant.

I meant, single stranded wire. Meaning 1 conductor and many strands in one wire, not solid.

Now I have to check to make sure I did not goof up the words and miss the "ed". Solid single strand is not for this application.

Thanks

John

[JohnB]

Hi again Wagon

OK my industrial slang is shining thru... I have corrected it.

Use to say "The single strand wires are slid in a piece of plastic tubing."

Now says

"The single conductor stranded wire is slid in a piece of plastic tubing."

At work we use either strand (stranded) or solid pending application. If it has a strand it is many fine wires to make 1 conductor and solid is well solid and no strands.

Thanks for pointing that out so non one else miss reads it.

John

[wagonman76]

Ok that's cool. I'm not an electrician but I definitely can tell what you used now.