Teardrop Trailer Frame Wiring Harness Kit


Wire your teardrop trailer frame up the right way the first time with this DIY wiring harness.  This wiring harness is the perfect solution for the DIY teardrop builder who wants their teardrop trailer running lights to work every time.

Included are all of the parts and a wiring diagram.  More details below.

We include a few extra parts and cut all of the wire and loom a few inches longer than listed.

See below to add our exact installation instructions and wiring tool bundle.

DIY Teardrop Trailer Frame Wiring Harness

A DIY wiring harness on a teardrop trailer should perform well for years, use the frame to protect and attach it, and should be mostly hidden.  There is nothing more frustrating than being all loaded up and ready to camp only to find that your tail lights or side markers are not working.  Usually that is due to poor parts and installation.  

The goal of this kit is to give you the exact high quality parts that go into commercial teardrop trailers and the added peace of mind that these parts should perform well for years to come (when installed as I recommend).

A Reliable Wiring Harness

Quality Parts Matter

“Trailer wiring shouldn’t suck.” – Mark


From the junction box, butt connectors, and wire sheath, this trailer wiring harness is designed to be as waterproof as possible.


Pure Copper Wire (Made in USA), heat shrink connectors, an 8 foot durable 7-blade RV plug, harsh environment wire mounts, loom and zip ties.

Flexible Installation

Multiple wiring harness sizes to fit your DIY teardrop trailer build. All with the same quality parts.

Features of the DIY Wiring Harness for Teardrop Trailers

DIY Teardrop Trailer Wiring Harness
Build It Right, Build It Once
Trailer wiring gets a bad reputation mostly because of poor quality parts and poor installation and use practices. This harness is the best parts and the same diagram that is used in commercial teardrop trailer production at Overland Trailer.
Standard RV 7 Blade Connection for Teardrop Trailer Frame Wiring
7 Blade Wire & Junction Box
8 Feet
Pre-Wired & Ready to Install with Grommets for weather proof. The Junction Box has a lid with a weather proof lid.
14AGW USA Copper Wire for Teardrop Trailer Frame
100% Pure Copper Wire
(Made In USA)
Most RVs use an imported copper-clad aluminum wire that isn't as reliable as pure copper made in the USA. This is the best!
Harsh Environment Adhesive Wiring Harness Mounts
Harsh Environment Mounts
Mounts & Zip Ties (Made in USA)
Harsh environment wire mounts keep wires up closer to the bottom of the trailer body. Harsh environment makes them resistant to UV light, chemicals and tearing.
10 - 12 AGW Shrink Butt Connectors
Heat Shrink Butt Connectors
10 - 12 AGW & 14 - 16 AGW
Butt connectors crimp wire connections together and shrink for a waterproof seal when heated.
Plug Holder Mounts to Teardrop Trailer Frame and Holds the Wiring Plug
Plug Holder
Protect Your DIY Wiring Harness
Unplug the trailer and put the plug into this holder. It protects it from moisture out of the plug and keeps it off of the ground.
Insulated Ring Connectors
Ring Connectors
10 -12 AGW & 10 - 12 AGW Shrink
All ring connectors for the junction box & waterproof shrink connectors are included...and then some!
Wiring Diagram
Know where it all goes
The same diagram used at Overland Trailer in manufacturing.


Add the Autowbrake proportional brake controller to this wiring kit.  Easy setup, not wiring in your tow vehicle needed.  Works with all brake systems.

DIY Teardrop Trailer Harness Options & Part Lists

Part: 5' x 8' Trailer Harness 5' x 10' Trailer Harness 6' x 10' Trailer Harness
Harsh Environment Mounts & Zip Ties (QTY) 25 30 40
12 - 10 AGW Heat Shrink Butt Connector (QTY) 8 8 8
16 - 14 AGW Heat Shrink Butt Connector (QTY) 4 4 8
7-Way Junction Box With 8' Wire & Seven-Blade Plug (QTY) 1 1 1
7-Blade Plug Holder (QTY) 1 1 1
14 - 16 AGW Heat Shrink Ring Connectors (QTY) 2 2 2
10 - 12 AGW Insulated Ring Terminals (QTY) 25 25 25
14 AGW Copper Wire - RED (FT) 7 9 9
14 AGW Copper Wire - GREEN (FT) 25 28 35
14 AGW Copper Wire - WHITE (FT) 25 30 33
14 AGW Copper Wire - BROWN (FT) 13 15 17
1/2" Split Wire Loom Conduit (FT) 30 35 33


Teardrop Trailer Frame Wiring Harness for the DIY'er
  • Heat Gun
  • Philips Head Screw Driver
  • 8mm socket
  • #2 Philips Screw Driver
  • 1/4″ Standard Screw Driver
  • Plus, wire cutters, crimpers, and strippers
Optional Tools: Drill & Impact Driver. (see below)

Simply put, a 7 blade RV plug is:

  • Durable – wires are well protected and don’t break easily
  • Expandable – It is easy to add trailer brakes, a 12V battery charge line, or backup lights/other accessories with the 7 blade plug.

As I say in my Expert Tips Video Lesson, it is good to future-proof a teardrop trailer build.  Let’s look at a few example scenarios.

For instance, you may not want trailer brakes right now but you might in the future.  With this plug, it is an easy addition to your wiring harness to add a brake system.

Another example is that you like the idea of charging your teardrop trailer from your tow vehicle when driving.  12V power an easy addition to this wiring harness.  Save yourself future headaches.

It’s super solid already but if you want extra peace of mind, I recommend putting a small screw in the middle of each harsh environment wire mount.  Drill into the frame, or teardrop trailer body, and apply mount adhesive, and drive a screw with an impact driver.

If installed as we recommend, our commercial trailer wiring harnesses typically last 10 years and longer with regular inspections and minor maintenance.

When installing the kit, it is best to avoid -as much as possible – sharp edges, sharp bends, and running wire in areas that could be exposed to collisions with rock and debris when driving.

All connections outside of the junction box are designed to be waterproof.  The junction box is water-resistant not 100% waterproof. 

Solutions are to either mount the junction box in a dry location or use additional silicone sealant (with regular inspection) to seal the box.  Also, ensure all lights are submersible and connections outside of the junction box are shrink connections.

If you’d like a step by step installation of this kit with all of my tips and tricks learned over years of trailer production, consider getting the trailer frame wiring plans & parts bundle.

Not at this time.  Sometime in 2021, we will be able to accommodate custom sizes.

Weight5.2 lbs
Dimensions16 × 12 × 4 in
Harness Size

5' x 8', 5' x 10', 6' x 10'


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.

You may also like…