Trailer Brakes and Wiring Installation –
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Trailer Brakes and Wiring Installation –

September 13, 2019

Today we are going to show you how to install
brakes on a trailer that does not have existing brakes. It is actually pretty easy to do it is just
very time consuming. There are a few things you want to look out
for before you start. One of those things is look being the existing
hub you have. Make sure you have a flange like this on the
axle. It is this 4 bolt flange on here if you have
that on your axle your pretty much home free. You will see it on 3,500 pound axles like
we have here. You also see it on 2,000 pound axles. On a 3,500 pound one you would probably use
a 10 inch drum and on a lighter 2000 pounds, you would use a 7 inch size. Also you notice we have the hub missing. We have to take that off because the hub and
drum assembly it is all in one piece. You have to take off the old hub get rid of
it and start off fresh. For this install we are going to install the
backing plate. Basically it slides on like so then you just
bolt it onto 4 places. A couple things you might want to take note
of is there is a left and right side to it also an up and down. The magnet always stays pointed to the ground. If you did not have a sticker like this one
does another way to tell is look for this bow here. The actuating arm or bow always points to
the front of the trailer so thats a good reference point for you. At this point lets start bolting on our hubs. Works down in a criss cross pattern makes
sure you have them evenly tightened. Go ahead and do the same thing for the other
side. One thing to note while you are adding the
hubs to a trailer. Take a look at the spindle. Take this spindle for example it is whats
called an EZ Lube spindle it has a Zerk fitting on the end. What happens is grease travels through the
middle of the spindle and comes out this hole here. If you have that it is great, but the thing
is when you get a new hub you want to make sure what kind of seal it comes with. Most of the hubs will come with a regular
single lip seal. You can see the just one lip right here. It has been around for ages and works great. However if you use this with an EZ Lube Spindle
what happens is grease gets pulled in and applies pressure to this. So what you want to do is get whats called
a double lip seal. As you can see here it has a lip on the inside
edge here along with the lip on the outside too. This is double protection that keeps grease
in and has a little bit extra pressure. You can also tell it is a double lip
seal because it has a spring. Every double lip seal
out there has a spring in it. So you have an EZ Lube Spindle or double check. Just to be on the safe side go ahead and order
a double lip seal. You can see where our hub is sealed right
on the end. You could call it the bearing or seal surface. This is where you are inside bearing rides
right here. As you can see here there is the hole that
the grease comes out between this seal and this bearing.


  • Reply nhjxmen February 25, 2009 at 11:57 pm

    thx for the help man. u guys rock

  • Reply Ron Benson July 26, 2009 at 8:56 am

    WRONG! Ya need to seat the bearing, turn till you hear it click, then back off 1/2 turn

  • Reply October 30, 2009 at 5:14 pm

    Assuming you have a 4-pole connection, you would need to take the 4-pole off and replace it with a 7-way connector. Then, run the brake wire lead from the pin labeled "Blue" out to the brake assemblies.

  • Reply December 14, 2009 at 7:09 pm

    I'm happy to hear our videos are helping you out! Please let us know if there is anything else you would like a video of.

  • Reply naughtydorf18 February 27, 2010 at 12:16 am

    could you do a video on how to pack trailer bearings that have them grease zerk spindles such as EZ lube, sure lube, etc. I have to redeo my bearings due to over doing it with the grease gun 🙁

  • Reply Malcolm Smith February 27, 2010 at 2:10 am

    I just found the 6 bolt 6000lb drums on your web site, I am buying them. My trailer NEEDS brakes, its terrifying in the snow.

  • Reply March 8, 2010 at 4:50 pm

    I will pass on your suggestion to our video people to see what we can do!

  • Reply Ray Reimann March 16, 2010 at 3:05 am

    This video on wring the trailer is terrific. It will help me alot. Being a novice to this I have this question. When you ran the wire over to the passenger side and zip-tied it to the axle, then you left a loop and ran the rest to the front of the trailer. How did you connect both sides of the trailer brakes? Are they all spliced together? How will this work on a 2 axle system? thanks in advance.

  • Reply March 19, 2010 at 7:16 pm

    To wire in both sides of the brakes you use scotch locks. The wire does not have to be cut in order to splice in with a scotch lock. The 2 brake wires tied into the loop on the side where the wire was first run with scotch locks. The second brake was spliced in at the end of the wire (as seen in video). On a dual-axle system, you would run one big loop and use scotch locks to splice in at each brake. I hope this helps. Let me know if you have any more questions.

  • Reply June 24, 2010 at 6:06 pm

    @zapityzapzap The 7-pole connector was a choice. The main tow vehicle had a 7-pole connector so, the 7-pole was put on the tailer to match the truck end. The trailer 7-pole was only using 6 of the functions at the time. Many people install a 7-way if they ever think there is a possibility of needing reverse lights or a reverse lockout. Others have it so they can have more than one 12v source for the trailer. Some have a 7-way simply because it is always easier to adapt sown to a smaller plug.

  • Reply August 10, 2010 at 5:20 pm

    @markeyjames22 For WI weather conditions, the best way to splice wires would be solder the wires together with a soldering iron. Then, use appropriate sized heat shrink wrap to cover and protect the connection. Heat shrink wrap is placed over the connection, heated and then shrinks down to cover the connection and seal out water. For one more layer of protection, you could wrap the heat shrink and wiring with a few layers of electrical tape. Your wires should be completely protected this way!

  • Reply littlefred811 January 27, 2011 at 6:58 pm

    Thanks for the great video! You just saved me a ton!

  • Reply January 27, 2011 at 7:10 pm

    @littlefred811 I'm glad it was helpful! Let us know if you ever have any questions.

  • Reply fomoco300k November 29, 2011 at 7:19 am

    is that Romex wire like you would use in a house that you are using to wire the brakes? ifso, do you use that for the lights as well or do you use the brown/green/yellow/white that comes typical to most wiring kits.
    (Have seen some people use old extension cords for the lights.)

  • Reply December 1, 2011 at 6:21 pm

    @fomoco300k It is not the Romex used in homes. It can be used for trailer lights, however, 3 wires are needed to carry signal and one wire for ground so typically the bonded 4 color wire is used in that application. Let me know if you have any other questions, I would be glad to help!

  • Reply yamaharidr450 September 17, 2013 at 2:46 am

    I want to buy this kit for my trailer ill have to buy a trailer break controller right?

  • Reply September 20, 2013 at 11:27 pm

    Yes, we recommend the Prodigy P2 brake controller most. Check it out at, part # 90885.

  • Reply giacomo tallarida February 27, 2014 at 1:23 pm

    I have an older trailer that has hydraulic brakes, and they are bad. is it possible to change them to electric brakes?

  • Reply DaytonCarCare October 7, 2014 at 5:27 am

    One thing he didn't mention was check for wear or an edge on the spindle. If the old bearings were worn too far down and bit into the metal then you need to change the spindle also.
     Or you will be singing "O why did you leave me loose wheel.." lol

  • Reply thestigmach1 May 27, 2015 at 5:14 am

    do you just split the wires for the brakes between all four wheels?

  • Reply BBB May 30, 2016 at 1:15 am

    How much should I pay for someone to wire my trailer? I'm so busy and I am disabled. Thanks

  • Reply Wlnston Rasmussen October 1, 2016 at 12:39 pm

    Great video.

  • Reply LightGesture November 20, 2016 at 8:36 pm

    the 12v power lead, aka black on the 7-pole connects to what on my trailer? white to white, blue to black, so what about the black on my 7pole???

  • Reply Vader Guy October 4, 2018 at 8:51 pm

    Good video, but lost me at the end, didn't show or say where the Brake wires went to, still trying to figure this out

  • Reply Matt Harris August 4, 2019 at 3:29 am

    Did you forget to tell us which color in the trailer plug was the brake wire or did I just miss it.

  • Reply Matthew Cain August 12, 2019 at 6:06 pm

    It's not personal preference. It is a fact that it is unsafe to use scotchlock style connectors compared to solder or at least butt connectors in this application.

  • Reply Abcde August 15, 2019 at 8:26 pm

    When you have tandem wheels do you put brakes on the front axle or the rear axle?

  • Reply butchtheiw September 4, 2019 at 12:48 am

    I don't get how you ended up with a two wire romex on the right side when you show a 6 or 7 wire jacketed wire(s) when you're tying into the main coupler??? It looked like it showed you passing the main line all the way back to that right wheel in the beginning, then you showed a 2 wire at the brake, and then it was back to the full harness. What's up with that?

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