Price: $16.42

Trailer Wiring Junction Box

Item # 38656

lowest price pledge

Our Price: $16.42

Orders above $50 qualify for Free Shipping

Quantity: 

In Stock
zoom in icon
zoom out icon
pop out icon replay 360 icon
horizontal rotate icon

Product Images

spectro accessories and parts  38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring trailer junction box
spectro accessories and parts junction box 38656
spectro accessories and parts wiring junction box
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring junction box trailer
spectro accessories and parts junction box

In Use/Installed

accessories and parts spectro wiring trailer junction box
accessories and parts spectro wiring 38656
accessories and parts spectro 38656
accessories and parts spectro junction box 38656
accessories and parts spectro wiring trailer junction box
accessories and parts spectro junction box 38656

Customer Photos

spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts junction box 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts junction box 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box
spectro accessories and parts wiring 38656
spectro accessories and parts wiring trailer junction box

  • Wiring
  • Junction Box
  • Spectro
This Spectro trailer wiring junction box provides a fast, easy way to connect the wires from the trailer connector to the wiring for either a 6-way or 7-way connector. Makes replacing your trailer's connector simple. Call 800-298-8924 to order Spectro accessories and parts part number 38656 or order online at etrailer.com. Free expert support on all Spectro products. Guaranteed Lowest Price and Fastest Shipping for Trailer Wiring Junction Box. Accessories and Parts reviews from real customers.



Spectro Accessories and Parts - 38656

This Spectro trailer wiring junction box provides a fast, easy way to connect the wires from the trailer connector to the wiring for either a 6-way or 7-way connector. Makes replacing your trailer's connector simple.


Features:

  • 7-Terminal junction box lets you easily connect your trailer wiring to a 6-way or 7-way trailer connector (sold separately)
  • Weatherproof, heavy-duty plastic protects wires and terminals from the elements
  • Mounting hardware included
  • Ring terminals (44-5310A) sold separately


Specs:

  • Box dimensions with lid: 7" long x 3-1/4" wide x 2-3/4" tall
    • Overall length (with mounting flanges): 8"
  • Distance between mounting holes (on center): 7-3/8"
  • Mounting flange dimensions: 3/4" wide x 1/4" thick
  • Outer diameter of terminals: 3/16"


9709 Spectro Trailer Wiring Junction Box







Related Products



Customers compare 38656 to these similar products







Customers Who Purchased This Accessories and Parts Also Bought...







Video of Trailer Wiring Junction Box


Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for This Old Trailer: Installation of a Junction Box

Previously on This Old Trailer we installed the backing plates in the hubs and on this episode we are going to install the wiring. Basically what we are going to do is hook up the wires for the backing plates and run them up to the front of the trailer. We are going to install junction box part number 38656. It is a good idea to have a junction box in case you ever have to change out the lead going up to your truck. It is easily changed out especially if you have a wiring harness that is all molded into one piece. We are going to upgrade this trailer with our junction box so we can do that. Install it in this location in the channel on the tongue. Hold the box up to it, mark some holes out, and drill it out to 1/ 4 inch bit and use 1/ 4 inch hardware to hold it in place. When we get the hardware installed we can tighten it down into place. 01:29

Next we need to start running our wires from the junction box and we will follow the existing holes that are in the frame down to our brake axle. The next thing we will do is make the connections to yhe junction box. We are going to peel back the gray cable a little bit and then we are going to run our white cable to ground that is labeled in the junction box. We are going to treat the junction box just like the inside of a 7-pole connector. White is going to be ground and blue is going to be for electric brake lead, however on the cable we have got a black and white wire. White is going to stay white to ground while the black wire will go to blue in the junction box. The junction box also comes with different grommets. You can see here this one is opened up for the cable and we will just replace the one that is existing in the box right now. We will just pull out the original grommet and slide in a new one. 02:39

We will also clamp our wire in position with the hardware provided with the junction box. We will add some ring terminals to our wires and attach them in to proper position. Next I am going to make a connection to the first brake hub and make sure you have plenty of slack so you wrap the wires where they will not get mashed up against the frame. We will make our connections and just leave plenty of slack and then later we will come back with some loom clamps. Lets cut back some of the insulation and we will make the wiring connections to the cable. The actual connections to the wire we are just going to use what is typically called a quick splice and we are just going to use that to connect our wires together. The brake magnet itself has two green wires. It does not matter which one goes to power as long as you have a secure connection one is going to power and one is going to ground. It does not matter on the green. Again on our second brake hub we will cut our wire to length. Make sure we have plenty of length left over so we have room for suspension movement and make sure it does not get smashed again. The same thing as before, it does not matter which wire goes where on the magnet. Just make sure one goes to ground and one goes to power. In this case we will be using the butt connectors to make our attachment. When using a butt connector with a smaller gauge wire like we are doing here, it might be a good idea to take the wire and fold it over itself and then install it in the butt connector and then crimp it down. 04:56

We will run our 7-pole cable up to the front of the trailer by the coupler. We are going to run it through the factory guide and then run it into our junction box. We will start making our connections for our brake leads inside there. Slip on the grommet for the wire cable and just like the other side put it into place. Next we will make our wire connections up from our 7-pole cable. White is still going to be ground so we will run it to our original white wire and that is labeled for ground. We will run the blue wire to where the black wire was ran to and that pin is labeled blue. We will make our blue and black wire connection permanent and with our extra bits of wire we have we can use that to make our jumper for ground. We will use the grommet on the top and poke a hole through it and the white wire through there. On the white wire we need to make a jumper off that post on to the frame of the trailer so the trailer can get ground from that point and then we can make that connection permanent. We have the left over wires and our 7-pole harness. What those are used for is the lighting on the trailer itself and for the purpose of this video we are just going to these both alone for now because we are only dealing with the electric brake part. Our next thing to do is apply the 12 volt power to our circuit and make sure the brakes work. Spin the hub with the power off and then when you apply power the hub should stop. That will finish our installation of the brakes on a standard trailer using a junction box and a molded 7 way connector. That finishes this episode of This Old Trailer adding electric brakes.


Customer Reviews

Trailer Wiring Junction Box - 38656

Average Customer Rating:  4.8 out of 5 stars   (459 Customer Reviews)

This Spectro trailer wiring junction box provides a fast, easy way to connect the wires from the trailer connector to the wiring for either a 6-way or 7-way connector. Makes replacing your trailer's connector simple.

- 38656

by: Wayne M08/07/2014


This trailer was built from scratch using only the metal frame. I purchased some items from etrailer an was very satisfied with the products. 144937


Comments

Great job! Looks like a high quality build.

-- comment by: Mike D - 03/26/2015

10361
Comments

Its still working great.

Wayne M - 08/07/2015

13983

- 38656

by: Michael C.11/17/2012


I purchased this product after researching current trailer rewiring methods. I recently had my entire 18' trailer wired and upgraded. The trailer is 8 years old and I wanted to replace the original 4 way trailer harness which the trailer manufacture had surrounded in electrical tape which also needed an adapter. After some research, I opted for this 7 way pigtail (50-67-005) which is the connector I needed my trucks and this junction box. (all contacts were current) The junction box is sturdy and well made, we installed 7 way wire within the box with a snug fit. The trailer now has a clean professional appearance and most test functions can be performed from the junction box location. The junction box was installed behind the trailer tongue frame to minimize the weather elements. This product appears to seal well as the product description indicates. I am very satisfied with this product and Etrailer's customer service. 59585



- 38656

by: Sherman M.11/04/2013


We wanted both a 7-wire and a 4-wire plug on the same trailer. This junction box made the installation very easy. If your connecting the Hopkins 7-wire harness to this box, you'll probably have to ignore the wire colors names and just use the location (R Turn, etc.). Both are marked on each terminal. There are 5 different openings to choose from to route the wiring to this box and it comes with both rubber grommets to run wiring through and rubber plugs for the openings not used. A downside is that only the side with 2 openings has wire hold downs on the inside. It would have been nice if at least the opening on the opposite end also had such a feature. It's fairly water tight and installed easily onto the frame, under the trailer. Because it's lightweight plastic, I'm not so sure how long it'd last in the direct sunlight if it was mounted on the tongue or other exterior location. 106238



- 38656

by: lwal05/22/2014


The wiring junction box is high quality, watertite, and makes for a professional wiring of brakes and lights. I am in the process of converting all my trailers to this junction box. 132015


Comments

This an excellent device that makes trailer wiring easy an easy to maintain. Highly recommend the box if one has the room to install it which some of my trailers dont.

lwal - 05/27/2015

12092

- 38656

by: Dennis W05/30/2015


I wired plenty of trailers in the past the old way connectors and tape but this box is in my opinion a must have! Easy to wire nice construction and for the price it keeps every thing out of the weather and organized. Thanks Etrailer! 198648


Comments

Thank you for the concern, Everything I purchased from you are working as they should. VERY HAPPY with all.

Dennis W - 06/17/2016

18731

- 38656

by: Matt W08/02/2016


Bought a fifth wheel camper last fall and the trailer cord was stiff enough that I could only find one position it liked to be plugged into the socket in the bed. Decided to replace the cord and get rid of the OEM metal junction box. I ended up ignoring the color code molded by each of the terminals and just went by the functions at were molded by the terminals. Everything is nice and neat with ring terminals connected to each terminal stud. Trouble shooting will be a breeze and future cord replacement will be easier. I like the fact that it eliminated a junction box full of wire nut connections. I tightened the lid screws until snug and did not have any issues. Grommets were sufficient and sealed up tight. I really wish there would have been a screw down cable clamp on each end instead of both on one end. 278702


Comments

Junction box is holding up great. No loose connections and the lid is nice and tight. Have not seen any issues with kid cracking or box leaking. Far superior installation than what came from the factory.

Matt W - 10/26/2017

29974

- 38656

by: Carl12/20/2016


For the price, I expected this to be higher quality. The junction box is functional and the labeling is excellent, however, the plastic is weak and the screws provided tend to tear up the plastic and may not work well at all if the box is opened or the cables are adjusted more than once. Problems with the junction box: - Strain relief screws protrude through the bottom of the box, compromising the moisture seal. When tightening the cable clamps, the screws are too long and cut through the bottom of the box. - Plastic is weak: When tightening the screws that hold down the lid, the bottom of the box becomes distorted. - terminal block is not well secured to the box. Only two rivets hold the terminal block to the box and even moderate torque on the terminal screws causes the terminal block to wiggle. 326689



- 38656

by: Robert S12/31/2016


Thanks for your help with parts for my trailer build. My wife and I are still making custom cabinets out of curly maple. We hope to finish this winter. We have taken it out 7 times this season. Thanks again. 329116



- 38656

by: John W.10/31/2012


Great looking and a smaller package than I thought. Fits better for the application. 58490


Comments

After a year in service all is still working fine. I will have to say that the rubber grommets are the weak link. They seem to be degrading a lot faster than I expected. Should be made of a material that is UV stabilized.

John W - 05/01/2014

3885

- 38656

by: Jason H03/19/2015


This product is a great way to fix a spot in the wires where they dragged on the ground. I simply cut out the bad areas and attached proper size wire nuts and secured this junction box. 179837


Comments

The box has continued to keep the wires working, safe and dry! Thank you for this great product!

Jason H - 03/18/2016

17164

- 38656

by: Joel j07/03/2015


Junction box was great had it installed and wires hooked up in a little over an hour. Service and shipment was better than expected. Will definitely use etrailer for more of my needs, very good company. The only thing that took a while was the molded seven connector wire colors don't all follow standards, but a test light and a few minutes and it was figured out. 209099



- 38656

by: Richard P.10/14/2017


Installed in about 30 minutes, made install a breeze and took the mess out of a rats nest of wiring spliced under the trailer. Comes with plenty of grommets and all hardware to put together. You need to supply the bolts or screws to mount this to your trailer. Each terminal is labeled for what connects to it taking the guess work out of matching wires up. 442709



- 38656

by: Loren04/01/2013


I installed this J-box over the weekend, and overall I'm pleased with its construction, particularly quality-per-dollar. The one 'concern' I have is that the grommets seem rather frail. After sliding over the 7-way wiring (H20046), I ripped the grommet as I slid it into the box. My guess is that it'll stay water tight for a minimum of several years living outdoor in the UV light, at which point I'll figure out some other way to keep it water tight, if needed. The J-box fits neatly inside the channel-iron frame of my trailer. The next time I need to wire a trailer, I'll certainly install one of these; a great value compared with piecing something together from the electrical supply section of my local Big-Box Store. 73670



- 38656

by: Al07/19/2013


excelent just what I needed glad I found it on you product line I tried to find something to use for splicing the wires under my trailer Ialso like all the tech. information you have available on your web site 90534


Comments

perfect

Al - 01/17/2015

8678

- 38656

by: Ron C06/06/2015


Wiring junction box received quickly and as ordered. Already installed with excellent fittment and great quality. Thanks! 201134


Comments

Installed very easily, still works greaT!

Ron C - 06/05/2016

18339

- 38656

by: Steve S.11/25/2013


I love these boxes. I've repaired numerous trailers my sons and I own, including cargos, flat beds and horse trailers. I really like the grommet locations, cable clamping and posts for wire connections. There is plenty of room inside to neatly route wires. 108409



- 38656

by: Dave S.08/29/2013


A decent product - perfect application if you're wiring a trailer with electric over hydraulic brakes I purchased this to replace the same box I bought just a few weeks ago where the plastic top cracked. You must be very careful not to overtighten the top 2 screws. After mounting the box on the trailer and doing all my wiring terminations, I put the cover on and screwed it down - everything was fine. Came out the next morning and the cover had cracked sometime during the night due to the tightness of the screws. I'm thinking of adding some rubber grommets to spread the load. It might also work better if there were 4 screws instead of 2. 97519



- 38656

by: Money09/30/2013


Exactly what I needed - direct replacement on my PJ Trailer. 101994


Comments

Working out great. No problems at all and looks factory.

Money - 09/30/2014

7042

- 38656

by: Chris O12/16/2016


Ordered lots of parts on Monday, received most of them by Thursday. The received parts were well packaged and undamaged. A few of the parts they didn't have in stock so they had those drop-shipped to me which should be delivered in the next couple of days. No supplier I have ordered any parts from has such a great technical reference web site or personal customer support. Yea, Rebecca - Well Done! Yes, I'm very happy with the pricing. Thanks for your great support and I look forward to doing business with them again. More info to follow as soon as I can get the parts installed on my trailer. 326667



- 38656

by: Hazel Self03/10/2014


Works great, thanks. 120105


Comments

It was actually 2 of the trailer junction boxes. They both are working fine. Thanks.

Hazel S - 03/11/2015

9973

- 38656

by: Dave M08/23/2014


Exactly what I wanted. Shipped promptly. Easy to install. 148167


Comments

Working great, just like it should.

Dave M - 08/23/2015

14499

- 38656

by: Smitty07/10/2016


I just finished the installation of the boxes, so I cannot report on their durability as yet. But, I can say they functioned properly after installation and are built well. For the money, they are diffently worth the buy. Other reviews indicated terminals are mismarked and sealing grommets are low quality and do not withstand intense exposure to the elements. I sused them for just a 4 wire hookup and the markings were accurate for that. As for the grommets, I found the blanking grommets to be a temporary design and could not possibly with stand the elements for a long period of time 270363


Comments

Still working.

Smitty - 07/10/2017

25894

- 38656

by: BODUNRIN.A12/03/2015


There is a saying which says that knowledge is power and seriously nothing can be more true.When I bought my trailer in 2012,I bought it brand new but unfortunately it was hardwired and for somebody like me I don't like such thing but unfortunately I never knew that there is a junction box like this that can be used for trailers to make a neat connection.One day,I was just checking for some items on etrailer when I came across this junction box and I watched the video and honestly I did not think twice to make up my mind to buy it because I know it will make a positive difference. 232969



- 38656

by: Ray S.09/24/2014


Junction box makes replacement of damaged trailer cord fast & easy. 152869


Comments

Excellent

Ray S - 09/24/2015

15199

- 38656

by: Steve L.07/16/2015


I wanted to get away from the wire nuts used on my trailer wiring. I bought 2 of these boxes and have installed one as a main box to distribute the connections to the trailer from the 7 pin plug. It was easy to install and had all the right hardware. You just have to add the right gauge connectors to your gauge wire and, for me, a couple of self drilling/tapping screws to mount. The second box will be for distribution of wires inside the trailer as I add 12v components. Super fast shipping on this and everything I have purchased so far, i.e. al191 marker lights. 212076



- 38656

by: Austin W04/09/2017


This junction box makes it so much easier to make your connections and it just looks cleaner too. Plenty of room for multiple wire applications. 365017



- 38656

by: Rick12/12/2010


Great products and service The junction box and molded trailer plug take a little extra energy to install- but the installation will be worth it, and replacements of the plug is much easier. The quality of the service from this company is Great! seldom do you find a combination of low prices, quality products and great customer service. My Order was delivered quickly and I received email advisory for each step of the process- including follow up on the delivery and they have installation videos and a great FAQ section. 4013



- 38656

by: Robert C08/18/2017


Purchased a Spectro junction box for rewiring my car hauler.Never rewired a trailer before. I can't believe how easy it was. If you pay attention to the fact that the junction box does not follow your trailer light color code. I installed the junction box first, attached wires from 7 blade molded plug then attached wires to the indicated functions and ran to the taillights. Attached to hitch for ground, turned on lights and blinkers using a test light to pin point wire function and I was finished. worked great. 422337



- 38656

by: Tom Drury07/07/2012


Service and response were good. The color code of the cabe did not match standard color code for trailors. I did need to use a volt meter to find left and right turn signals, running lights, and the reverse reverse signals. At this time I dont know if the problem was how the cable was made or how my truck was wired. The quality of the cable was fine. The break out box seems to work fine and I think this will be an improvement to splicing wires toteather with butt splices. The quality of the box is fine. 47029



- 38656

by: Kevin L06/04/2017


I used this to connect the 4 pin coiled connector. This worked perfectly. I had five wires coming from the trailer, and this helped connect those. I drilled a hole through the back and through the trailer frame and fished the wires in through the back. This way there are no wires showing, they are fully protected inside the frame and the box, and there are no inline connectors to shake loose. The online help was just what I needed to know how to connect up the wires correctly. This was perfect! 388603



- 38656

by: RJ07/15/2013


Installed as I had planned and it went well. Wired the supply line to the box to all of the correct wiring terminals as it is labeled in the box. I was prepared by other reviews, things may not match up, which they didn't, but no biggie. Once I flipped a few wires around things worked nicely. 89609



- 38656

by: Brian O10/09/2017


This product is a real problem solver. I'm so tired of patching up old wiring harnesses on my trucks and trailers. In spite of my best efforts to make waterproof connections I still ended up having to cut off old tape and renew connections. Now that I found this connector box on etrailer I can bring multiple wires together, make a solid connection and close it up. If I have to check or change connections just take the cover off. Don't forget to get the right size crimp ring connectors. 441087



- 38656

by: Mike F.04/02/2013


This product was delivered in a very short time after order was placed. It is everything that I expected. There is plenty of room in the box to run the various wires both incomming from the vehicle to trailer connecting wire harnes and out to the various lights and brake connections. I have not had a chance to install this box yet, but I definatly know that it will make the installation of the trailer wiring much more simple and relible than what I had done on my previous trailer. 73803



- 38656

by: Andrew H.07/24/2017


One of my favorite discoveries here on etrailer.com. Makes it dirt simple to organize your wiring and leave room for expansion. All the screw posts are captioned with embossed labels - R. Turn, L. Turn, White (Ground), etc. Really like the cable clamps that act as strain reliefs. The only thing I can think of that could be improved on: A little drain in the bottom for water? I drill one or two 1/8-inch holes in the box to allow any water that gets inside to drain out. 410022



- 38656

by: Bob H.08/20/2012


Had some real issues with this one. Should have noticed when purchasing this harnes is not wired using standard truck/trailer color format. Other than that it went together fairly nice. If the connector would come apart I was thinking of fixing the wiring my self. 52400



- 38656

by: Ed B02/13/2017


Well made product with a great design. The only criticism I have of the product is the cheap flat head screws provided with it. They should be stainless and the smaller ones Phillips head. If the screws were of be it would have gotten a five star rating. 341553



- 38656

by: Robert O.07/13/2016


Wiring junction box; made wiring easy; must have item. 271408



- 38656

by: Elijah K11/12/2014


I would love to rate a 5 star, but the box is not the greatest to install when it requires you to go out and purchase your own mounting screws. I installed this on 2 of my trailers and it seems to do the job perfectly, I even had to replace the 7 round plug on one of the trailers and it made it really easy to redo the wiring. I would, however, recommend this to anyone looking for something to use for ease of access. Thank you etrailer. 160676



- 38656

by: Jack Stout02/13/2017


I have used errailer at different times. Each time their products have been the absolute best. Their phone clerks are knowledgeable of product and service. Shipment time has always been extreamly prompt, sometimes as little as 2 days, retailer is unaware that I grew up in a fleet service shop, I owned and operated my own for 20plus years. I also have a [retail] store that uses their service, a simple ITS THE BEST is all I should say! 343776



- 38656

by: Jake Bise05/26/2017


Excellent customer service! Ordering the products on line was easy and the instruction videos and installation tips were very helpful. I received my order as promised and every thing I ordered was packaged and shipped professionally. I will definitely return to etrailer for any future purchases. Also the quality of products was excellent and the price was a lot cheaper than anywhere else I shopped, even with shipping cost. 386542



- 38656

by: Mike R05/11/2017


Products received were high quality as advertised and the customer service was awesome. US postal service as the delivery method was less then impressive. Found my package laying on the ground by my mailbox roadside. This by no means was Etrailers Fault but something to consider when they chose a delivery method for their customers. The experience with Etrailers other then this was awsome. Will be ordering more for sure. 380539



- 38656

by: Seth07/22/2012


It was nice for organizing the wires and install. The rubber wire hole plugs are not the best. One month outside in the sun and the top one dried out and cracked. I guess install it some where it is protected from the weather. 48905



- 38656

by: Chris B11/07/2016


Rewired my trailer and used this junction box to go from my main cable to all the individual lights and brakes. It worked great, the only thing I didn't like about it was that it only had two cable clamps on the inside 314692


Comments

I still have all the electric supplies from etrailer on my cargo trailer. I have had no issues with any of your products whatsoever. I hope this helps

Chris B - 11/11/2017

30714

- 38656

by: Rick J.07/22/2016


Love this product. I have used this on one other trailer I have and the last one I installed on it was a 30ft flat bed trailer and used two of them. One up front and one at the back end of the trailer. Makes it much easier to connect the side lights up and all light at the rear of the trailer. All so if adding stuff later it makes it easier from either end of the trailer. Really good product and built very well. 275047



- 38656

by: Jason C07/23/2015


When replacing a trailer plug with anything more than a 4flat connector this is a must have. Multiple openings and grommets make it very easy for installation and configuration. Also when figuring out mixed up colored wires on old trailers, this makes switching wires around to the correct lead super easy. Don't trust colors on old trailers! It does not come with any self taping screws or hardware. 213902



- 38656

by: Russell F.11/07/2012


Solidly built and works well - definitely a time saver if there's a need to rewire anything or add a circuit in the future. Just beware - the terminals each have a label with a color and a function (e.g. "Tail", "Brown") but some of these do not match the standard 7-way wiring suggested on this site. I think "Stop" and "Red" are listed together, even though the brakes are most often "Blue". 58961



- 38656

by: Dave H.01/19/2015


Purchased along with 10' of the Deka 7 wire cable. Nice box, although would be better if it had an additional wire entrance on the right side of the box. The left side has 2 entrance points, the right side has only one. Easy enough to get around by drilling a hole in the side and sealing the wires with silicone caulk. Other than that, it provides a well sealed junction point for the wiring. 170380



- 38656

by: S Lewis02/06/2017


All ordered items worked great. Love the LED tail lights. Didn't have any problems fixing the trailer thanks to the many technical articles I found on etrailer. Not sure what happened with UPS shipping since I got notified that the parts had shipped on Saturday but didn't get them till Wednesday evening (paid extra for 3 day shipping), but definitely recommend ordering from etrailer. 341399



- 38656

by: Everett L03/02/2017


Great fenders for what I am constructing--which is NOT a trailer. It IS a 1946 Ford Cab Over Engine (COE) truck with a flatbed. Perfect fit dimensionally. Fenders arrived in great shape even though I was skeptical. Packaged nicely. Junction boxes have been used through out truck as a water tight area to terminate wires and house relays. When done I will send pictures. 350891



- 38656

by: Lonnie W.03/27/2012


I have received the Trailer Wiring Junction box but have not had the opportunity to install it yet. Prior to my purchase of this item I researched the installation video located on the etrailer site. My 16' trailer will be in use within the next month and I am looking forward to many years of good service. This is just the item I needed to repair the wiring on this trailer. 35255


62
471
Show More Reviews

Ask the Experts about this Spectro Accessories and Parts
Do you have a question about this Accessories and Part?


  • How to Rewire an Old Cattle Trailer
  • It sounds like you are on the right track to rewire your cattle trailer. You are correct about the wire colors on the 7-way connector that you purchased. The colors that you see on the 7-way connector are typical for RV style trailers rather than utility, cargo, or livestock style trailers. The black wire should be connected to the terminal in the 7-way connector labeled black. This is the terminal in the 11 oclock position when you are looking at the back of the trailer connector (see...
    view full answer...

  • Re-Wiring Old 4-Wire Boat Trailer Plug With a New 7-Way Trailer Plug
  • Considering that the 4-wire round connector on your Dad's old boat trailer may be nearing the end of its life (due to use and corrosion) you will be better off replacing the 4-way round connector with a 7-way plug such as # H20046 from Hopkins. Installing a new trailer-side male plug will also avoid the complication and cost of having to use an adapter and it will make the trailer much more user-friendly to the majority of tow vehicles likely to pull it in the future. Installing the...
    view full answer...

  • Parts Needed to Add Interior Lights to Enclosed Trailer with 7-Way Connector
  • To mount a 12V battery in your trailer to power its lights you will possibly need a battery box like # PH13035 to hold it securely and also a way to tap into the 7-way's 12V trickle charge circuit, such as a junction box like # 38656, along with ring terminals like # DW05702-1. Note that a 7-way power feed can maintain a charged battery but cannot deliver enough power to charge a depleted one; for that you need a charger like the # CTEK56158 that you referenced. For maximum light operation...
    view full answer...

  • Complete Wiring for Lights, Electric Brakes and Controller for a 94 GMC 1/2 Ton Truck and Trailer
  • Lets start with your 1994 GMC 1/2 Ton Truck. You will need to start with the # 118315 4-Way connector. Once the 4-Way is installed, see instructions link, you will need the Brake Controller Installation Kit, # ETBC7, and a brake controller. I recommend the P3 Brake Controller, # 90195, which is one of the best controllers we carry. We have detailed instructions for installation of the controller and the wiring kit, see links, and we have installtion videos of a brake controller and wiring...
    view full answer...

  • Recommendations For Re-Wiring Horse Trailer With Brakes
  • Since you said you have a 7-way blade connector on your Silverado I would start with the 7-Way Molded Trailer Wire Connector, part # H20046. This is an 8 ft long harness with the 7-way trailer connector. If you need a shorter harness you can check out part # H20044 which is a 6 ft long harness with the connector. You will want a circuit tester like part # 3808 to make sure you match the wiring on the trailer side connector to the functions on the vehicle connector. I then recommend using...
    view full answer...

  • Adding a 7-Way Trailer Connector, Junction Box, and LED Lights to a Trailer
  • I think adding a 7-Way and a junction box and not to mention LED lights are great ideas! If you are going to replace all of those items, you may as well go the all out and replace all of the trailer wiring as well. Starting with a trailer side 7-Way connector you can use # H20042 which is 3 feet long. It doesn't have to be long though because it is going to the junction box. Speaking of junction boxes you can use # 38656. I have included a picture showing how it can be wired up and...
    view full answer...

  • Recommended Surge Brake Actuator With Electric Lockout For Drum Brakes
  • We do have a surge actuator that has an electric lockout for drum brakes. I recommend the Titan Zinc-Plated Brake Actuator, part # T4339720. This actuator is adjustable to fit 1-7/8, 2, and 50-mm hitch balls and is a bolt-on for 3 inch wide trailer tongues. The breakaway kit is included with this actuator. If you have a 7-way connector on the back of your Expedition, you will need to change the trailer connector to match. I assume you have a 4-way connector. I recommend a 7-way connector...
    view full answer...

  • How Much of Each Gauge of Wire Fit Inside a Wire Loom Comfortably
  • I would certainly recommend the 1/2-inch wire loom # 459075-1. It will hold two jacketed 2 wire 10-gauge wire and three jacketed 2 wire 12-gauge wire. See pictures to the right. In addition, I was able to fit comfortably eleven individual 16-gauge wire # DW02359-1 into the 1/2-inch wire loom. I also took a digital caliper to measure the exact radius of each type of wire: 10-gauge is .17 of an inch, 12-gauge is .14 of an inch and 16-gauge is .09 of an inch. The 10, 12 and 16-gauge...
    view full answer...

  • Availability of Wiring Adapter to Convert 12-Pin NATO Trailer Connector to 7-Way Blade Style
  • We do not offer any adapters to convert a 12-pin military trailer connector to a 7-way RV-style plug like that on part # H20043 but we can help you gather the parts you'll need to wire in a new trailer plug to match that on your pickup. We can also offer you an easier alternative. To re-wire the trailer conector you'll need a wiring junction box # 38656, a trailer-side plug like the 4-foot # H20043 (or longer versions such as 6-foot # H20044 or 8-foot # H20046) and ring terminals like...
    view full answer...

  • Installing a 7-Way Trailer Connector on a Trailer with 6 Wires
  • You can certainly add a 7-way trailer connector to your trailer with 6 wires. You would simply have 1 pin on the 7-way connector that did not function. I recommend adding a 7-way molded trailer wire connector like part # H20046, and a junction box like part # 38656. We do this on all of our trailers and our customers trailers and it will make future wire maintenance much easier. I have attached an installation video of these two parts for you to check out. Once you have all of your parts,...
    view full answer...

  • Parts Needed to Add Timbren Suspension and Electric Drum Brakes to Tear Drop Trailer Build Project
  • Timbren offers their axle-less trailer suspension systems in many configurations, some with brakes and drums, others with idler hubs for applications without brakes. All of their kits are shown on the linked page. A trailer can require brakes based on its gross weight, GVWR. You want to choose the Timbren kit that matches the trailer's intended GVWR. You do not want to pick a system that is rated for more weight than your trailer will have as this will tend to produce a rougher ride....
    view full answer...

  • Parts Needed to Re-Wire Car Hauler Trailer Lights and Brakes
  • We can help you with selecting parts to re-wire your trailer's lights and brakes. Trailer size affects the number and types of lights required to be DOT-compliant. I linked for you an article that covers the lighting requirements for trailers of various sizes. This will help you determine what is required for your specific trailer. For lighting you might want to consider one of our complete lighting kits. Kit # TL29BK uses standard incandescent light bulbs and kit # TLL9RK uses high-efficiency...
    view full answer...

  • Testing Trailer Lights and Electric Brakes without Connecting Trailer to a Vehicle
  • If you have a separate car/truck battery you could apply power to each of the pins on the trailer connector (or the wires directly some point behind the connector) and that should power on whatever is associated with a given pin.
    view full answer...

  • Installing Brake Controller On Kia Sorento For Towing Enclosed Trailer
  • In order to use a surge coupler, you'd need to replace the coupler on your trailer, as well as the brake assemblies and possibly the brake drums. You'd also need to run brake lines. Honestly, your most economical and safe way to proceed here would be to complete the wiring on your trailer, and install a 7-way and a brake controller. Installing the brake controller would be a pretty simple process. I'd recommend you go with a proportional brake controller, like the Tekonsha Primus, part...
    view full answer...

  • Parts Needed for Adding Trailer Brakes to Haulmark 12 x 6 Trailer
  • A complete kit for electric brakes isn't available, but we can certainly get you the parts you're needing. I'll link you to our FAQ article that explains what's needed to add electric brakes to your axle. I don't have a reference that would tell me exactly which axle is being used on your trailer, but it's pretty easy to figure everything out. The first thing you'll need to do is check your existing axles for brake mounting flanges as shown in the article. If you don't have the flanges,...
    view full answer...

  • Parts Needed to Add Electric Brakes to a Wells Cargo SW-10 Single-Axle Service Wagon Trailer
  • A good starting point for your project to add electric drum brakes to your trailer is a review of the linked article which covers this process in detail. You will need to select brakes based on the weight rating of the axle on your trailer, which should be indicated on a sticker or plate, and you'll need to select new hub/drum assemblies that use the same bearings as the hubs currently on your trailer. This will ensure compatibility of the new hub/drum assemblies with your spindles. If...
    view full answer...

  • Why Are Their 7 and 10 Terminal Junction Boxes Made for Trailer Wiring
  • I attached a picture of a 10 terminal junction box that is using every single available terminal. If you had turn signals that were separate from your trailer brake lights this would be the junction box to use along with the # 118158. Otherwise the 7 terminal box like part # 38656 would be all that you would need.
    view full answer...

  • What Size Ring Terminal Will Fit the Hidden Hitch Wiring Junction Box # 38656
  • I pulled the Trailer Wiring Junction Box # 38656, and Ring Terminal # 44-5310A, from our warehouse. The correct ring terminal size that will fit is part # 44-5310A, which is a 3/16 ID terminal for 12-10 gauge wire. I produced a short video showing that the # 44-5310A ring terminal fits on the post of the Junction Box. Also linked is an FAQ on trailer wiring.
    view full answer...

  • Adding a Battery on an Enclosed Trailer to Power Interior Lights
  • The best way to power the interior lights in your trailer is with its own independent battery. You will not want to use the breakaway battery. The breakaway battery is only designed to operate the breakaway and will drain extremely quickly, they're only required by law to operate your brakes for 15 minutes. There's a few ways you can install a battery onto the trailer. One is to connect it to the 12 volt pin on the trailer's 7-way in place of the breakaway battery that is currently...
    view full answer...

  • Will Curt Vehicle to Vehicle Tail Light Converter # C56196 Cause LED 3rd Brake Light to Blink
  • The Curt Vehicle to Vehicle Tail Light Converter # C56196 that you purchased (along with some additional trailer lighting) separates the combined stop/turn signals fed to it into discrete stop and turn signals that can be fed to the individual lights. Since your toy hauler has incandescent lights on it the addition of a LED third brake light should not pose any issues related to current demand. This vehicle-to-vehicle converter connects at the toy hauler lights at the rear of the trailer....
    view full answer...

  • Installing 7-Way Trailer Plug on Trailer with Electric Brakes
  • I recommend the Hopkins 7-way molded trailer wire connector # H20044. It will measure 6-feet long and provide you the functions required for your electric brakes. If you prefer a longer connector, the same item is available in an 8 foot length as part # H20036 or an 11 foot length as part # HM20048. Please note that the color codes on these molded connectors are different from those usually found on a trailer. The wiring code is on each of the product pages. If you don't have some...
    view full answer...

  • Adding Electric Drum Brakes to a Scamp Camper Trailer
  • Setting up a trailer with electric drum brakes is going to be the easier and most cost effective way of adding brakes to your Scamp trailer. Since the trailer already has the mounting flanges that will limit the amount of parts and work that will need to be done. Starting with the hub and drum assemblies since your bearings are both L44649 and you have an EZ Lube style axle you would need # 8-257-5UC3-EZ with the 5 on 4-1/2 bolt pattern. They are designed for 2,000 pound axles but will...
    view full answer...

  • Does a Trailer Junction Box Have to be Used when Switching from 4-Way to 7-Way Trailer Connector
  • Junction boxes are great for keeping things organized and for making changing out trailer side connectors and troubleshooting easier. They are not a necessity so you can keep it if you want, it is entirely up to you. If you want to use the junction box, I have linked some videos that might help. The wire colors and the sides of the trailer they are on are actually a little different then what I would expect. Normally the green wire is the right side right turn and brake light wire and...
    view full answer...

  • Trailer Brake Lights Do Not Work When Connected have a 96 ranger with seprate turn and brake
  • Whenever any type of adapter like # PK12716 is used to mate different types of connectors on the vehicle and trailer, connection problems can develop because of all the extra contact points. The best way to go is to install a new connector on the trailer that directly matches that on the tow vehicle so that you can avoid using an adapter. This is easily done by using a junction box like # 38656 and a new 7-way plug like # H20044. All you need to do is verify the function on each trailer...
    view full answer...

  • Replacing Lights and Trailer Connector on Boat Trailer Over 80 Inches Wide
  • Although there isn't a specific kit available that addresses all your needs, you can use a light kit designed for an over 80 inch trailer like # TLL36RK and modify it so it will work. You'd need some extra wire, # 16-3B-1, an ID light bar for the middle of the rear beam that would tie into the running light circuit, part # MCL70RB, a molded trailer connector, part # H20046 and a junction box, part # 38656. The install would be pretty straightforward. The molded connector would run to...
    view full answer...

  • Troubleshooting Trailer Brake Lights and Turn Signals That Are Not Working Correctly
  • The two most common causes for problems with trailer lighting functions are corroded vehicle or trailer connectors and a bad ground on the trailer or vehicle. The good news is that these two problems are fairly simple to check and correct. First, check that the main trailer connector ground wires on both the vehicle socket and the trailer plug are solidly connected to a clean bare metal surface that is free of grease, rust and paint. A weak ground can cause all sort of odd behavior from...
    view full answer...

  • Parts Needed to Add Electric Drum Brakes to Trailer
  • The linked article gives you a recap of what is needed to add brakes to a trailer. Since your trailer's 2200-lb axle already has brake flanges installed, adding brakes to it will require you to select left- and right-hand brake assemblies and hubs/drums to replace your idler hubs. The new hubs have to use the same inner and outer bearing as your old hubs to ensure they will fit on your existing spindles. Check the mounting bolt pattern on the flanges to ensure they match the 4-bolt pattern...
    view full answer...

  • Tow Dolly and Brake Controller for Towing Vehicle Behind Motor Home
  • We do offer a tow dolly with electric drum brakes, the Roadmaster # RM-2000-1, which fits a 2-inch hitch ball. This dolly has a 4,380-lb weight capacity for the loaded vehicle. It includes electric brakes, 4-pole wiring harness with extra wire for the brake circuit, loading ramps and wheel nets that fit tires from 12 up to 16-inches. The brake controller I recommend is the Prodigy P2 # 90885. This reliable unit is highly rated by our customers and it works with both electric and electric-over-hydraulic...
    view full answer...


Do you have a question about this Accessories and Part?




  • Why etrailer.com?

    At etrailer.com we guarantee:

  • Highest quality accessories and parts for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate accessories and part information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Satisfaction Guarantee
    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Expert Research:
Michael L
Video Edited:
Zack K
Expert Research:
Robert G
Expert Research:
Michael H
Expert Research:
Reno H
Expert Research:
Jameson C
Expert Research:
John H
Expert Research:
Adam R
Photos by:
Amber A
Expert Research:
Jeffrey L
Photos by:
Sam P
Updated by:
Shelly K
Updated by:
Sarah W

At etrailer.com we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.




^
About Us
photos and videos
1,056,204

Original Photos & Videos

Produced to make sure you know what you are getting and you get exactly what you need.

installations
35,570

Installations Completed

To make sure products work and fit the way they are supposed to.

etrailer call center
2,476,511

Phone Calls & Emails Answered

1,125,924 phone calls and 1,350,587 emails to help find the right solution.

etrailer training
400+

Average Hours of Product Training

We get to know our products firsthand so experts can better help you.

etrailer service
71

Years of Quality Customer Service

Assisting our neighbors and customers, face to face at the counter.

etrailer experts
193,357

Pages of Expert Information

Created to make sure you have all the answers to your questions, from real experts.