bing tracking image
  1. Custom Fit Vehicle Wiring
  2. CURT
  3. Custom Fit
  4. Trailer Hitch Wiring
  5. 4 Flat
  6. Powered Converter
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Our Price: $53.66
Custom Fit Vehicle Wiring

Will this fit?

To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.

This item qualifies for Free Shipping
Shipping Weight: 0.82 lbs
In Stock
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

In Use/Installed

Customer Photos

Need help with installation?
Locate installers near me
Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. Connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance. 1-800-496-5010 to order CURT custom fit vehicle wiring part number C55370 or order online at Free expert support on all CURT products. Great prices and Fastest Shipping for Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
  • All Info
  • Reviews (316)
  • Q & A (0)
  • Photos
  • Why etrailer?

CURT Custom Fit Vehicle Wiring

  • Custom Fit
  • Trailer Hitch Wiring
  • 4 Flat
  • Powered Converter
  • CURT

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. Connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.


  • Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
    • Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
  • Connects quickly and easily - no cutting or splicing of wires
    • Locate connection point in rear cargo area
    • Plug in connector
  • Includes a tail light converter to ensure that your vehicle's wiring matches that of your trailer
    • Powered module connects directly to battery to avoid overloading vehicle's electrical system
  • Constructed using surface-mount technology (SMT) for consistent, reliable performance
    • Maximizes trailer light yield and intensity while producing minimal heat
    • Ensures superior operation in rough road conditions
  • Comes with dust cap for 4-way flat connector


  • Maximum amperage:
    • Stop/turn lights: 3 amps per circuit
    • Tail lights: 6 amps per circuit
  • Limited 1-year warranty


This custom-fit T-connector plugs into your vehicle's wiring harness, which is located in your rear cargo area. You will have to remove interior trim paneling to access the connection point. Once you've plugged in the T-connector, insert the included 10-amp fuse into the in-line fuse holder.

Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your cargo area.

It is recommended that you use a small amount of grease on all electrical connections - the plug on your automobile and the 4-pole connector itself - to help prevent corrosion.

Powered Tail Light Converter with Surface-Mount Technology

A tail light converter is built into this T-connector. This converter is a circuit-protected, battery-powered unit that bypasses the electrical routes that are used by a basic wiring harness. As a result, there is virtually no draw on your tail light circuits.

Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of the trailer. This converter combines the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights. Note: This will not affect how the tail lights on your vehicle operate.

Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.

Curt SMT Circuit Boards

Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.

Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.

55370 CURT T-Connector - Surface Mount Technology - 4 Wire

Item # C55370

Installation Details C55370 Installation instructions

This Product Fits The Following Vehicles

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - C55370

Average Customer Rating:  4.8 out of 5 stars   (316 Customer Reviews)

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. Connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.


Great internet service, good customer service, great experience will use this company in the future for sure !

Excellent product, works great, this is the third product purchased from etrailer they all are quality products
Jack W - 04/09/2022


True plug and play! Video was great except my harness was on the driver side of my 08 outback not the passenger side.

2009 Subaru Tribeca

Product seems correct but it was shipped in the same box as the trailer hitch with no packing material and the box the wiring came in was smashed by the hitch and it’s contents were scattered inside the shipping box.

I will have our Customer Service team reach out to you.
-- Etrailer Expert Jenny N - 04/19/2022

2003 Subaru Forester

Purchased the Curt T-Connector for my 2003 Subaru Forester. Item was an affordable replacement for original equipment. Installation was easy. Item worked well after it was installed.

After much use, Curt T Connector continues to work well.
Daniel S - 05/26/2022


This Curt wiring harness I purchased for a customer of mine was simple to install and the quality was exceptional

Still works wonderfully!
CRAM - 04/17/2022


Your dedicated employee Noah went to bat for me, resolved my order issues and took care of me. Nicely done due to his personal attention and effort. Ben


It's been a year of usage and I have no issue. The wiring harness is also working just fine.
Great products and great customer services!
I would highly recommend anyone who is planning to install a hitch receiver.

2006 Subaru Outback Wagon

I'll start off and say that this product looks and feels five star, but I'm docking it one because the installation docs and video are very mismatched and conflictive. The one-page paper installation doc was barely applicable, while the video was much, much better. Use it!

Pulling out the few pieces of the car necessary to gain access to the OEM plug was relatively easy. Where things got messy was where to actually put the "control" block for this thing. The video shows a self-adhesive backing which was not present. There are included zip-ties but no really good place to use them. I didn't want to leave it loose in there to become yet another rattle in the car, so I ended up securing it with that foil tape used for duct-work. It seems to have done the trick.

Routing the cable was easy, and I dropped it under the spare tire and through a grommet, resealing it with silicone when I was done. I'd have loved to see some kind of cable management included for under the car and around the hitch, rather than the four independent wires being just ad-hoc wrapped around things.

Electrical testing worked flawlessly, and all outputs were signaling correctly.

2006 Subaru Forester

Great product. This took under 5 minutes to install. The Forester 2006 had the electrical connector under the floor tray on the passenger side at the very rear under the taillight hidden by a plastic flap. Lift up flap, plug in, then snug the hardware into the side well.

You can run the wire and trailer connector through the 1" hole at the rear of the wheel well capped by a large rubber plug so the wire disappears under the spare.


Plugged right in to factory harness and worked like it should.


Box arrived with a couple holes torn and hitch hanging out one corner, but l accepted it hoping for the best. Installed hitch and wiring harness by myself in about 2 hours from start to finish... probably could have done it faster with help, starting the bolts was frustrating but doable nonetheless. Product seems well made, no complaints there. Dealing with Etrailer has been a good experience so far and will most likely be a returning customer.
Attached pic of hitch hiding under bumper, just how l like it!


Finding the connector in the car is NOT easy, unless you know exactly where to look. Watch their Youtube video.
Works fine, at a very reasonable price.


Worked great easy install everything is great about etrailer I’ve ordered several this was my third vehicle so happy with them and their service

2004 Subaru Forester

Product, shipping, website, return policy all were perfect. Will for sure use this site in the future. Only reason i didn't give it full excellent review was because I found my hitch cheaper two on 2 other sites. That being said those sites didn't have the amount of reviews etrailer did which further explained the ease of install by customers....and gave me that desired warm and fuzzy feeling when ordering from the World Wide Web :)

Wiring installation instructions complete with pictures made me feel like superman with a phd. Well done etrailer. Well done.


Good pricing, and quality with fast shi pping

2006 Subaru Outback Wagon

Exactly the right fit for my 2006 Outback. I chose the option to run the wire out the bottom of the spare tire well, and that was simple. I used this kit with 2 other products: a no-drill electrical mounting bracket, and a 4-pole mounting bracket. The installation looks great.


The installation of the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector was quick and easy. Very straight forward. After a year, the left taillight electrical does not work and the connection has to be monkeyed with to get the right side to engage.


The item description for this wiring harness included everything I needed to confirm my model would be compatible. The Curt connectors are easy, just plug and play. The wires are all organized with plenty of length to make good connections. I highly recommend this wiring harness for your 4-Pole trader hook-ups.


Good product, easy ordering, quick deli very!


Worked great.

2006 Subaru Outback Wagon

Shipped on time as advertised and complete. Instructions were well written and accurate for hitch itself, but missing a couple steps for the electrical connector kit, (as for taking apart the car trim) so took some time to figure out. (The instructions were from the manufacturer and not itself). Connector worked fine on installation.The fit of the hitch was very precise, so precise that at first I thought it wasn't the right model. But I persevered, and it did fit. The close and precise fit is appreciated, it should help eliminate possible looseness, rattling, and weakness. This is my third Curt hitch from on 3 different cars. I would definitely buy from them again.

These are not the first Curt products I ordered from Etrailer. After a year, I have no complaints about the products, and certainly none about Etrailer. I find the Curt products well designed in form, fit, and durability, and etrailer a fast and efficient way to order them.
Kent R - 12/27/2017

Subaru Outback Wagon

2008 Outback
Wires are good quality.
Instructions could be a lot better. "remove left and center black plastic, after locating wire..." The words "wire connector located just forward of left tail light assembly would of been better than all of the instructions given. The plastic on the side goes from the tailgate past the back seat and you don;t need to remove it. You only have to remove a screw in the corner but I had no idea which panel it was behind, center or left towards the front back or middle. Step 2 for outback refers to fig A but mine looks nothing like it, mine looks like fig C.
They also say Tools needed : phillips screw driver. That's it. And step 2 they talk about using a pry tool.
The kit also includes a grounding electrical connector, a electrical splice fitting and a self tapping sheet metal screw with no reference as to what to do with them.
Spending ten minutes to write some instructions would make this about perfect.

I use this frequently and have had no problems with it.
rodney a - 08/12/2018

2008 Subaru Outback Wagon

Complete kit,easy installation. The wiring harness connected directly to the auxiliary wiring found in the left rear inside pockect of our 08 subaru Outback. All lights on our 2 trailers worked the very first time . We've had this kit for a little over a year, With zero problems. Many thanks to Curt for quality product. Also many thanks to (Laurae) for their fast friendly service.

Its a great product. Still performs flawless after thousands of trailer hookups.
dennis r - 01/17/2018


Easy to install. Works as advertised...


Great product

Show More Reviews

See what our Experts say about this CURT Custom Fit Vehicle Wiring

  • Can the 4-Way Trailer Wiring Harness be Routed Under a 2008 Subaru Tribeca
    On the 2008 Subaru Tribeca you will either need to stow the 4-Way in the cargo area and pull it out of the rear hatch and shut the hatch on the wiring (the weather stripping will protect it, stay away from the locking mechanism) OR you will have to drill through the bottom of the cargo area if no other options are available. Be sure to seal up the hole after you are finished to keep out fumes and moisture.
    view full answer...
  • Where Does Trailer Wiring Plug Into on a 2008 Subaru Forester 2.5XT
    On the 2008 Subaru Forester the connector you are looking for should be rearward of a long junction box with wires going in and out of it on the driver's side based on your pictures. It is potentially concealed by being wrapped up in electrical tape. Follow the wiring coming out of that box and you should eventually come across the connector. But it may not be easily visible and you may need to cut away tape or protective loom to get to it. The wiring branches off and the connector usually...
    view full answer...
    Image 1 for
  • Location of Wiring Harness Connection Point for 1998 Subaru Legacy Trailer Wiring
    The connector you are looking for can be in a couple places. I attached a picture that one customer sent in that shows where it was on their 1999 Subaru Legacy. The picture shows the left side taillight assembly area. Another customer with a similar Legacy said they found it located in the position described for Subaru Forester (passenger side in spare tire compartment under carpet next to wall.)
    view full answer...
    Image 1 for
  • Trailer Wiring Harness for a 2006 Subaru Tribeca
    Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector Item # C55370 is indeed a confirmed fit for the 2006 Subaru Tribeca. This harness fits a few different Subaru vehicles but we haven't had a Tribeca in to make an installation video. But the manufacturer has tested it on a Tribeca. The video I have linked can be used as a guide since it is a different model and installation will be a bit different. I have also linked the instructions for you.
    view full answer...
  • Troubleshooting 4-Pole Trailer Wiring Harness on 2008 Subaru Outback Wagon
    Thank you for your purchase of towing components for your 2008 Subaru Outback Wagon including Curt wiring harness # C55370. The yellow wire on this 4-pole harness carries both turn and brake light signals for the left-side light. Since your harness' left side output is always solid (it does not blink) then this suggests that the harness is damaged. Please note that we do offer a custom-fit harness for the 2008 Outback Wagon (as long as it is not the Sport edition), part # 118461 from...
    view full answer...
  • Where is the Plug on a 2008 Subaru Outback Wagon for Trailer Wiring Installation
    The plug is behind the driver side taillight. You will need to remove several interior panels to access it. To see where the plug is for installing the Curt Wiring Harness part # C55370 check out the video I attached. It's for the Tow Ready version of the harness # 118461. The install will be the exact same.
    view full answer...
  • Trailer Wiring Plug Location on a 1997 Subaru Legacy Wagon GT
    If your 1997 Subaru Legacy Wagon GT is not the Outback version, then you will not actually have a plug-in point for a trailer wiring harness. Non-Outback versions of the wagon must hard wire to install a 4-Way trailer connector, using a kit like part # C55370. To hard wire the kit, you would use the included circuit tester to determine which wire carries each function behind your vehicle tail lights. You will also need to run a power wire to the positive terminal on the vehicle battery....
    view full answer...
  • Trailer Hitch that Fits 1999 Subaru Legacy Outback Wagon
    For your 1999 Subaru Legacy Outback Wagon we have the Draw Tite hitch aprt # 36234 as a confirmed fit. This would be a great choice that has plenty of capacity and installs relatively easy as well. If you were wanting trailer wiring too we have the Curt # C55370 as well.
    view full answer...
  • Trailer Wiring Recommendation for 2006 Subaru Outback Wagon
    She would first need to start with a 4-way on her 2006 Subaru Outback. For that the part # C55370 would be what she would need. Then to convert it to a 7-way you would want the part # 37185. The 4-way would plug into this and then the black wire of the adapter would get ran back to the positive post of the battery through a breaker like part # 9510. That's all that would be needed for the charging circuit to be complete.
    view full answer...
  • Can a Trailer Connector be Routed Under a 2011 Subaru Tribeca
    The wiring harnesses like # C55370 for the 2011 Subaru Tribeca are meant to be stored in the vehicle cargo area and then pulled out the back with the rear hatch closed on it (the weatherstripping on the vehicle will protect it) when you need it. In order to route it down under the vehicle you will need to find a grommet or some exit point at the lowest point in the cargo area. If there is no grommet or you find one that is not large enough you will have to drill through the bottom of...
    view full answer...
  • 2001 Subaru Outback Wagon Trailer Hitch Receiver Class II - 1-1/4
    I recommend the Curt Trailer Hitch Receiver Class II - 1-1/4" # C12270. This is a confirmed fit your 2001 Subaru Outback Wagon, excluding Sport model, and has the higher tongue weight rating of our available hitches, 350 lbs. For your trailer wiring you will need the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector, # C55370. For the ball mount, I suggest measuring the height first. Please see the attached links for a help article in how to do so. If the...
    view full answer...
  • Trailer Hitch Options and Maximum Weight Capacity for a 2004 Subaru Forester
    After researching your question, I found a couple of sources stating that the towing capacity for a 2004 Subaru is 2,400 lbs. Nonetheless, I recommend double checking your specific owner's manual. Also, if you're looking for a Trailer Hitch, I recommend the Draw-Tite Trailer Hitch Receiver - Custom Fit - Class II - 1-1/4" (300 lbs TW // 3500 lbs GTW) # 36311 Please check out the attached video that highlights why I recommend this particular Trailer Hitch for your vehicle. To complete...
    view full answer...
  • 2011 Subaru Tribeca Hitch and Wiring Recommendation
    The correct hitch for your 2011 Subaru Tribeca is the Curt Trailer Hitch Receiver part # C13069. This is a custom fit hitch designed specifically for your vehicle. It offers the very versatile 2" reciever tube opening which is compatable with all types of hitch mounted accessories for you to use. Should you have the need to haul a trailer you will need wiring and a ball mount. For this I recommend the Curt T-Connector Vehicle Wiring Harness part # C55370 which is also a custom fit part....
    view full answer...
  • Parts Needed to Install 7-Way and Curt Echo in 2005 Subaru Outback Wagon with Curt 4-Way
    You can easily use a wireless brake controller like the Curt Echo part # C51180 in your 2005 Subaru Outback Wagon that you are installing the Curt 4-way part # C55370 in. The only other thing you need is a 4-way to 7-way adapter part # ETBC7L. This adapter was actually put together by us for people like you who want to adapt the 4-way to a 7-way to install the Curt Echo. You'll plug in the 4-way and then run one wire to the battery and you'd be set.
    view full answer...
  • Recommended Trailer Hitch Receiver For 2005 Subaru Outback XT Limited Wagon With MT Turbo
    For your 2005 Subaru Outback XT Limited Wagon, I recommend the Draw-Tite Max-Frame Trailer Hitch Receiver - Custom Fit - Class III - 2" # 75560. This is a confirmed fit for all models with the exception of the Sport model, so it will work for the turbo MT model. This trailer hitch receiver is an easy bolt-on installation with the included hardware. It is a square-tube design with a black powder coat over an e-coat base for superior rust protection. The 2 inch receiver will give you...
    view full answer...
  • Parts Needed to Convert 4-Pole Wiring to 7-Way on 2007 Subaru Forester
    We can help you convert your Forester's 4-pole flat type trailer wiring to a 7-way blade style to match the connector on your new trailer that has electric brakes. Once you have a 4-pole installed, such as Curt # C55370 or Tow Ready # 118461, you can convert that to a 7-way using our # ETBC7 brake controller installation kit. This includes everything needed to install the included 7-way trailer socket on the Forester and allow you to install a brake controller like the popular and easy-to-use...
    view full answer...
  • Parts Needed To Tow a Small Boat Trailer With a 2004 Subaru Outback Wagon
    The Curt Trailer Hitch Receiver part # C12270 is a confirmed fit for your 2004 Subaru Outback Wagon and it will work to pull a boat trailer. That said, you will need a few other parts to complete your setup which I have listed for you below. Curt T-Connector Vehicle Wiring Harness part # C55370 Curt Drawbar part # C45519 Curt Pin and Clip part # F-4 Curt 1-7/8" Hitch Ball part # C40001 In regards to installation of the Curt Trailer Hitch Receiver, this is very simple to do yourself as...
    view full answer...
  • Trailer Hitch and Wiring Recommendation for 2004 Subaru Forester
    Best option would be the trailer hitch part # C12038 which is a fit for your 2004 Subaru Forester, but you'd need to verify that your vehicle has the capacity for the pontoon boat. The hitch by itself has a 3,500 lbs capacity. For trailer wiring you'd need the part # C55370 which is a confirmed fit. For a ball mount part # C45503 and then hitch balls # A-82 for a 2 inch ball or part # A-80 for 1-7/8 inch ball.
    view full answer...
  • Wire Loom and Wire Loom Clamp for Routing Power Wire for 7-way install on a 2003 Subaru Forester
    You are on the right track with all of the products you are planning on purchasing to install the Prodigy RF brake controller part # TK94FR and then also leave the option to use a different brake controller in the future. For wire loom I would go with 1/4 inch loom like part # 7509-10 sold in 10 foot sections, and then to secure the loom you could either use zip ties (this is what I did on my car) or you could use the Metal Loom Clamp # A0250 for a more permanent solution.
    view full answer...

Do you have a question about this Custom Fit Vehicle Wiring?

  • Why

    At we guarantee:
  • 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 custom fit vehicle wiring 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

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

Info for this part was:

Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Joshua S
Video by:
Joshua S
Employee Michael B
Video by:
Michael B
Employee Nicholas E
Test Fit:
Nicholas E
Employee Shane H
Test Fit:
Shane H
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Cole B
Installed by:
Cole B
Employee Wilson B
Updated by:
Wilson B
Employee Kristina F
Updated by:
Kristina F
Employee Isabelle B
Updated by:
Isabelle B

At 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.