Car Trailer - Electric Brakes Install - Diesel Forum

Rotary7 · 08-15-2005, 02:09 PM

Well, I went through all the posts and did a search can't find the answer, so here's the question and hopefully I'm in the right section!

Bought a two axle car trailer, custom made with 3500 pound axles. Neither one has brakes like I asked. Since I had little time after picking it up, the builder said I could just retrofit the electric brakes on one axle.

I get the idea...buy the drums, buy the pads and install them. But how does it hook up to the electrical system? I guess I'm looking for a blue wire (etrailers)? Does the blue wire come out the back of the pad assembly? Also, do I now need a new plug (6-7 pin?) and do I rewire the trailer lights as well?

v/r
Ralf W.

cphilip · 08-15-2005, 02:40 PM

Well I know you will need a 6 pin.

Unless you wanted to put a seperate deep cycle battery on the trailer and keep it charged. Some commercial ones are like that with thier own lights and such. Then its 7 pin to do that.

And of course should be fairly easy to adapt over with existing lights to the 6 prong female.

You might even want to wire a break away activator into the set up if you have a onboard battery to activate the brakes and go 7 prong.

Not certain what the actuator wire color is. But blue does sound familiar. But I betcha the brake kits would have plenty of instructions in there with them to tell you. Your energizing a magnet is what your doing.

But I was under the impression that it was the entire hub you had to put on there? Including mounting lugs for the disc if your going disc brakes? I could be wrong on that part. Only realy done some drum electrical ones myself.

But I can tell you that my car hauler has E brakes only on the one axle and stops pretty darn good. So does my camper if I recall correctly.

Rotary7 · 08-15-2005, 03:11 PM

You have it correct. Electric drum brakes, not discs, they get too expensive. Also, I'd like to wire in the breakaway switch. They have their own battery included from what I've seen.

Does the new plug (6-7 prong?) come with wiring for all this? Will that plug into the 05 truck end plug?

There are no kits in terms of being cost effective. I found one that has wiring and shoes, without the drums and they wanted in excess of $300. Most of the components, bought separately, cost in the range of about $180.00.

OldmanII · 08-15-2005, 03:39 PM

Try a local Dexter Axle dealer close to you for all your parts.
http://www.dexteraxle.com/

cphilip · 08-15-2005, 04:00 PM

The only wiring I would think you would need is the lengths to reach the axles of simple stranded wires. And for neatness and protection a roll of plastic wire loom and some strap ties. The pigtail of the 6 (or 7) should have a short length of it in each color code coming out of it. You would want some good wire connectors. Weather proof and vibration proof ones.

If someone makes a kit with long reaches for it all then you would not need that.

But I would think all you want to run is the additional wires to the brakes and use the wires already pulled to the lights by cutting off the old four prong end and splicing in your new 6 prong.

Your truck's 7 pin hole should work fine. All you might need is a 7 to 6 prong adapter in line to eliminate the 7th (battery charging) wire. Those are simple plug in adapters found anywhere. I use one on my Car Hauler flat bed. It does not have a battery.

SmokeyWren · 08-15-2005, 07:31 PM

Probably cheaper, and definitely a lot less trouble, would be to replace one axle with a brand new axle that includes electric brakes. A 3,500-pound straight axle with electric brakes costs only $210 plus shipping. Click here. And the folks at ETrailerParts.com (subsidiary of TheDieselStop sponsor SouthwestWheel) will be glad to talk you through the wiring it up to the 7-pin plug on the back of your PSD. In fact, I'll bet the instructions are in the pkg with the new axle.

Before you call Southwest Wheel, measure the length of your axle from hub face to hub face. The hub face is the base of the lugbolts, where the wheel fits up against the hub.

If it were mine, I'd probably replace both axles with axles that include electric brakes. And I'd hook it up with the break-away switch that will lock the brakes if the trailer comes unhooked from the tow vehicle. That means I'd also need the 7-pin plug on the trailer to match the factory 7-pin plug on the back of most late-model PSDs - along with a "marine" deep discharge battery on the trailer.

4-pin "U-Haul" plug = trailer lights and turn signals

6-pin plug adds electric brakes - common on gooseneck horse trailers and utility trailers, etc.

7-pin plug adds battery charger circuit so the trailer battery will be charging while you're on the road. Common on RV trailers, LQ horse trailers, LQ race trailers, and any trailer where the owner wants break-away brakes on the trailer.

In some states, the break-away switch is required on any trailer grossing over so many pounds. Your 7,000-pound combined GAWR would require the switch in most of those states. [img]/ubbthreads/images/graemlins/cool.gif[/img]

**SteveRacer** · 08-16-2005, 03:46 AM

My only comment is I just got new complete Dexter 8K backing plates/brake assemblies from "etrailerparts.com" and although they were $10 more than the cheapest out there, their customer service and integrity is the best I've found.

I also bought my trailer wheels from "them" (Southwest Wheel).

I'm glad they are a sponsor, but that wasn't my motivation - I just think that outfit is a class act.

-steve

Rotary7 · 08-16-2005, 08:38 AM

Appreciate that information. I have a much better handle on what I'm doing with the replies I've received.

Though the new axles would be attractive, the shipping and the cost are more than purchasing new brake components. From Eastern marine, I can purchase the shoe and backing plate pieces for $37.00 each (Dexter) and I can locate some drums from Northern for about $90.00 (pair).

I agree, I will need the breakaway kit and will be purchasing as well from Eastern. The way the trailer sits, I see that it also needs proper lighting. It just has taillights.

For $950 for the trailer itself, I think I still did alright, especially since it has the ability for me to mount my cradle winch on the trailer itself via a welded on receiver. I'll still be less than the cost of other trailers out there especially considering the costs of getting them from Texas or Missouri. TN was far enough from VA (diesel prices considering). Its just a PIA to drill the holes and mount the lighting and get the brakes in place.

grahambl · 08-16-2005, 09:18 PM

Its usually about $40 more to replace the whole axel, then sell the other one for a profit.

Brian

AlH · 08-17-2005, 04:25 AM

[ QUOTE ]
From Eastern marine, I can purchase the shoe and backing plate pieces for $37.00 each (Dexter) and I can locate some drums from Northern for about $90.00 (pair).

[/ QUOTE ]

Hold on...the components sold by Northern are NOT Dexter, they are Reliable. Are you SURE the Reliable drums will work with Dexter backing plate/shoes etc? They might I don't know. [img]/ubbthreads/images/graemlins/shrug.gif[/img]

Also have you looked and made sure your axles have the brake flanges? Some builders cheap out and use an axle that can't have brakes added, saves them a few dollars. If they did that you gotta replace the axles anyway.

And not to start THAT debate again but the brakes go on the BACK axle if only doing one, and I wouldn't do just one. [img]/ubbthreads/images/graemlins/crazy.gif[/img]

Rotary7 · 08-17-2005, 07:54 AM

Well, the ebrakes site lists the axles at $210. Then there's shipping involved, and the labor. I think its more time consuming to swap axles than to put on the parts. I could be wrong as I haven't done it before. Shipping is scary as I would think with something that big, they would have to be trucked. That can be costly. Haven't checked on the price as I think, unless I pick them up, it will be too expensive...all things considered.

Ralf

Rotary7 · 08-17-2005, 08:00 AM

You're right, Dexter brakes and Reliable drums. I'm not sure if they'll work together, but it isn't really a problem on cars as long as the parts are the same size, so would it be a problem with trailer components? Good point.

The brake flanges worried me, so I contacted the builder and he confirmed they had them (I was at work). When I got home, I checked and sure enough, the flanges with holes are on there. Any special bolts needed to mount this stuff to the flanges? High grade, etc?

Back axle for now? Another post said front axle. Confusion again. I'll put on another set of brakes after I do some reserve days.

Ralf

tta583 · 08-17-2005, 12:39 PM

Perhaps I am a little confused, like that never happened!!! You have to get the backing plates and drums sepratly? Now I will admit I have never put on a set but I have, on several occasions, asked trailer shops about adding brakes to a second axle or, like you where there is a non brake trailer, adding them to one. I never recall being told I have to buy the pieces and asseble them, they have always been in a single box, ready to go.

Beyond that I have had the luxory (!!!) or rewiring a couple small open car trailers. You had asked about this but I think it got a little lost in the talk of the brakes. Here are a few things that have helped me out in the past:

Wire the truck for a 7 round if not already wired. I keep adapters in the door pocket: 7 round to 4 flat, 7 round to 6 round. No matter what I can hook up as long as the trailer pins are "standard".

Wire the trailer 7 or 6. Use an adapter if you wire it 6. If you wire it 7 then you just leave the unused pins empty.

I guess it is already wired for lights (4 flat). I have been in that situation. I made sure I understood what wire did what (parking lights, L/R signal, and ground) then cut off the connector and attached them to the appropriate pin in the new 6 or 7 round.

Make good grounds. Make sure the gound on the trailer is clean, same for the truck. That power has to have a way to flow back!! I would upgrade the trailer side gound (just a heavier wire) if you add brakes instead of using the (typically) small wire found in a 4 flat harness. When I redo grounds (like if I start it from scratch) I generally drill a hole some place in the frame up by the tongue then use a bolt there as a post to home back all my gounds.

One pin on the trailer harness will go to the brakes. All of the trailers I have seen came from the builder with those cheesy wire taps making the connection between the feed wire and the wires at the backing plates. Same connectors used to connect the ground. Those things are trash. They are not weather proof, provide little connectivity, and WILL cause you a problem down the road. Spend the extra $2.50 and run to a local home improvement store and get some silicone filled wire caps.

I have wired the brakes in 2 ways. Factory trailers will (tend, as I have seen) to run the main feed down one side to the backing plate. They will then branch off that connection and feed the otherside via a wire passing through the axle. In some cases I have used this wire and simply re-made the connections to eliminate the cruddy taps. In other situations, where I started from scratch with all new wire, I made my split up at the tongue and ran an individual set of wires to each side. I have had luck either way.

As for parts, I get most of my stuff from:
http://www.drawtite-hitches.com/
or
http://www.reese-hitches.com/

I have no tie to them, just had good luck with them over the years. You may find a lot of what you need in the Electrical section of the sites. Both sites are the same place. Many times I have called them with specific PNs from the manufacturer's site. IN other words they have a lot more than they have on line. They may have brake retrofit kits as well.

All in all, it is actually easy. Swap out the backing plates, run a heavy wire for to feed (+) voltage to them. I would run a diffrent color back up to the tounge for the ground or you could just fround to a clean spot on the frame. You will find the wires on the plates are the same color. They just go to small electro magnets, polarity does not matter to them. Swap in the 6 or 7 round connector.

good luck.

Rotary7 · 08-17-2005, 03:39 PM

Appreciate the information on the electrical. The truck has the 7 pin outlet from what I understand, it being an 05 SD.

As for the brake parts, I called Champion Trailer initially as they have a good website. I asked the same question as you posed. Is there a kit to make life easy. They said "No", too many permutations in terms of size. They gave me the information on how and what to buy in terms of the hard parts. I still can't imagine the drums and brakes being different if they come from different manufacturers but supposed to be for 10" brakes.

Thanks again!

AlH · 08-17-2005, 07:29 PM

See I can't imagine the different brands *being* compatible but maybe they are. Afterall Ford brakes don't usually fit Chevys etc! Brake diameter is not the only consideration, there are different widths of the brake shoes/drums available also. Even within Dexter there are different 10" brakes, 1.5 and 2.25 inch shoe width so you definitely can't assume all 10" brakes are the same.
Dexter is the undisputed leader in the field, even if was a few dollars more I'd try to stay all one brand and would go for the Dexter.