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Curt Trailer Connector Adapter - 4-Way to 7-Way RV and 4-Way Flat

Curt Trailer Connector Adapter - 4-Way to 7-Way RV and 4-Way Flat

Item # C57672
Retail:$72.00
Our Price: $35.82
You Save: 50%
Trailer Wiring
Shipping Weight: 1.3 lbs
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This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet. Great Prices for the best trailer wiring from CURT. Curt Trailer Connector Adapter - 4-Way to 7-Way RV and 4-Way Flat part number C57672 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (389)
  • Q & A (0)
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CURT Trailer Wiring - C57672

  • Wiring Adapters
  • Multi-Function Adapter
  • 4 Flat
  • 7 Round - Blade
  • Plug and Lead
  • 4 Flat
  • CURT

This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet.


Features:

  • Adapts 4-way flat to both 7-way RV and 4-way flat
    • 4-Way flat output connects tail lights, brake lights, and turn signals
    • 7-Way connects tail, brake, reverse, turn signals, and auxiliary power
  • Dust covers keep connectors clean when not in use
  • Split loom keeps wires contained and well protected
  • Simple installation
    • Wiring harness plugs into existing 4-way flat connector and hardwires to existing wiring to get additional functions needed for 7-way
  • Included hardware and metal mounting bracket secures wiring to the vehicle or trailer hitch
  • 1-Year limited warranty


Specs:

  • Distance between bracket mounting holes center to center: 2-1/4"
  • Harness length: 17"
  • Yellow wire is for reverse lights
  • Blue wire is for brakes
  • Black wire is for 12 volt power
  • White wire is ground


57672 Connector Diagram



57672 Curt Multi-Function Socket - 7-Way RV Blade and 4-Way Flat - Universal Fit

Installation Details C57672 Installation instructions


California residents: click here


Customer Satisfaction Score:


Customer Reviews

Curt Trailer Connector Adapter - 4-Way to 7-Way RV and 4-Way Flat - C57672

Average Customer Rating:  4.7 out of 5 stars   (389 Customer Reviews)

This multi-function, vehicle-end connector converts any 4-way flat, vehicle-end plug to a combination 7-way outlet and 4-pole flat outlet.

by:

Good product easy to install only reason for 4 stars is that the 4 pin connector doesn’t stay in the provided slot on the bracket



by:

Your site us very helpfull for information and support and i reallt apreciate etrailer for all tge purpose.good product ,help support,and fait delivery even heure in Canada.
Tgank to all of your team.i am presently installons the controller on my car after the installation i Will feed about how it work.
Have a nice day

Luc

7/30/2023

Very well great product,goid brake controll ,smooth,ibreally like the way it work,and Allo it take juste à small place under dash for me 10 star a grest product

Luc

7/30/2023

Great product the curt7pin with the 4 pin on the side really helpfull for installation good product ,to be sure keeping moisture away in the connector i Also use electric compound grease in it to prevent corrosion and still very good no connection problem yet even with the kind of weather we have here up North in Quebe crain ,snow,..good product well made.



by:

I used this on my 2017 RAV4. This harness provides me the flexibility of using flat-4 or a 7 way connector for towing flexibility. The RAV4 is a small tow vehicle and I like the added security of electric brakes even on lighter single axle trailers which the 7 way allows. I plugged this adapter into the flat-4 connector provided by the "T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector Item # 118578" and used heat shrink tubing around the crimp connectors for the brake controller wires to keep moisture out.



by:

The connector fit the existing mount on my 2007 Dodge Ram 1500 bumper perfectly. Four bolts and nuts, plug in the wiring, and I'm ready to roll. Thanks, etrailer! Another great product!



by:

Works well for our needs!



by:

THE people to go to for trailer and towing stuff. Myself and friends all order here, can't say enough about the great customer service, always getting the right parts, and the overall quality. It is always a pleasure.



by:

Like this a lot.



by:

Great all in one unit



by:

Works perfectly. No problems at all.

Just
an FYI, the installer didn't hook up the reverse wire although we asked. This is a common practice according to our camper's manufacturer so be adamant with your installer if you want the wire connected.



by:

This would be a 5 star rating if all my trailer plugs fit equally well. The preformed trailer wiring plugs are a perfect fit, (4 out of my 6 trailers have them), but two aftermarket plugs are a struggle to get the retention notch to fit inside cover hook that keeps the plug in place. ((Otherwise the plug pops out)).
Bottom line is I would buy this connector again because of the price point and ease of installation. From now on I will be buying the preformed trailer wiring harness for the perfect fit.



by:

Needed to slightly modify the bracket clearance holes to have the plastic holes line up properly and fit cleanly. Not a big deal but someone else may have struggled with that if they expected a simple install.



by:

I had an existing 4 pin, this plugged in and gave me the 7 pin I needed for picking up my teardrop. I did not use the other wires and just taped them to the casing. Worked perfect.



by:

Good product overall, installed on my 2016 Volkswagen Golf to tow a 13' Scamp fiberglass trailer. Although do be attentive, as other reviews have stated, that using all the functions of the 7-pin connector (electric brakes on the trailer) may require extra work. In my case, it required running an extra lead from the car battery with a fuse in line. I was was able to run it through the body of the vehicle, although I gather it's also possible to run it under the entire vehicle. Just something to be aware of; as my first time towing anything, it was a learning curve to understand how to put it all together.



by:

Worked great for a while. Then the pins started to pull out and stick in the trailer plug. Have to pull them out of the trailer plug and push them back in.



by:

Overall, satisfied. The installation videos were helpful, and the product seems quality. I only have one complaint, which is what kept this from being a 5 star review. This may be obvious to most people, but it wasn't to me. This WILL get you to a 7 pin connector, but there is a good bit more work to do to get all the functions of a 7 pin connector to work. Meaning, to get power to my 7 pin connector and trailer, I had to run a wire to the battery, and place a circuit breaker inline with that wire. Again, this may seem obvious to some, but it took some figuring out for me, and any time I asked this question to etrailer, they could never seem to give a straightforward answer. But for my Mazda CX-5, about 15 feet of 12 gauge wiring and a small fuse kit did the trick. Lots of splicing of course.



by:

Air lift installed on a 2018 Jeep Wrangler JKU with a 4” lift. Alison B put wanted to make sure I got the right bags and put me in touch with Air Lift who helped me get the correct bags. It was easier and quicker to remove rear springs and install the bags, just remember to apply lubricant to help with installation. Alison B was great to work with and extremely helpful in making sure I got the right parts. I have done business with etrailer in the past and will continue to use them in the future.



by:

Fast shipping, clear instructions, easy install, works great.
Thanks!

Bones

2/9/2023

Still working! Thanks!



by:

This is a great harness. And was easy to install and is still working great a year later.



by:

I took my car over to the dealership and they sent it out to another shop. When he brought my car back, the electrical wires were installed upside down. It took the installer over 6 hours to install my receiver hitch.
It looks great now that I’ve turned the wiring the correct way to install your electrical wiring.



by:

Put this on after #c56027 to change to 7-way rv plug as all my trailers have been switched to 7-way. 7-way is much easier to plug and unplug than 4-way. Easy to install. I have been using it once a week and it is working very well.



by:

Not even 2 years after install all rusty. Electric brake pin broke due to rust.
Impossible To remove 4 bolt holding connector due To rust. I do not recommend

Etrailer Expert

Katrina B.

7/19/2022

Its unfortunate that your pins and bolts are unusable due to rust. I see that you are located in Canada, we recommend making sure that you are using dielectric grease often to prevent and keep the rust from spreading along the harness. Unfortunately, rust is not covered under warranty, and even if it was, this is well passed the one-year warranty for this item. I would recommend contacting our customer service department for them to assist you in ordering a new harness, such as part # 118467.



by:

This sure made changing from the factory 4-way connector to a 7-way/4-way connector quick and easy. All I had to do after installation was to add wiring for the electric brakes and trailer battery charging.



by:

Great product! Only issue is lack of mounting holes (2) on top of metal bracket. Maybe they forgot to drill holes at the factory.



by:

Within 3000 miles the wires came loose from the connections and shorted the light system, unfortunately withing a few minutes of this happening, I was stopped by a office. I could have gotten a ticket but instead was given a warning. Had to re wire on the spot around the connections to be able to move the van.



by:

This product worked great for me. I had a little trouble fitting it to my Toyota Sienna (it would have helped if the 4 pin flat connector could be located on either side of the 7 pin round connector), but functionally I’ve had no issues. One weakness I could see is the included butt connectors are not heat shrink type so they’re not weatherproof. This could lead to corrosion in the wiring eventually. Otherwise good product!


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Show More Reviews

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