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  1. Custom Fit Vehicle Wiring
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  4. 2003
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FITS 2003 GMC Sierra
Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector - 10' Long

Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector - 10' Long

Item # C56000
Retail:$167.95
Our Price: $117.95
You Save: $50.00
Custom Fit Vehicle Wiring
Confirmed to Fit
2003 GMC Sierra

with factory 7-Way

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CURT custom fit vehicle wiring for your 2003 GMC Sierra are available from etrailer.com. Installation instructions and reviews for your GMC custom fit vehicle wiring. Expert service, and great custom fit vehicle wiring prices. etrailer.com carries a complete line of CURT products. Order your Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector - 10' Long part number C56000 online at etrailer.com or call 1-800-940-8924 for expert service.
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2003 GMC Sierra - Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector - 10' Long

  • 7 Round - Blade
  • Fifth Wheel and Gooseneck Wiring
  • CURT

Mount this 7-way, RV-style connector in your truck bed for quick, simple hookup of your 5th-wheel or gooseneck trailer. Custom harness plugs in-line with your existing factory wiring so that you can retain use of your GMC Sierra's factory 7-pole.


Features:

  • Provides 7-way, blade-style connector in your truck bed for hassle-free hookup of 5th-wheel and gooseneck trailers
    • Connector mounts in truck-bed sidewall, tailgate post or wheel well
  • Retains factory 7-pole trailer connector at rear of truck (if present)
  • Plugs into factory wiring - no cutting or splicing
    • 10' Long, insulated wiring harness reaches from rear bumper to truck bed
    • Requires that truck have factory tow package
  • Custom fit for your vehicle
  • Includes zip-ties and self-tapping screws for installation


Specs:

  • Harness length: 10'
  • Wire configuration:
    • Yellow: reverse lights
    • Green: tail lights
    • Brown: right turn and brake lights
    • Blue: electric brakes
    • Black: 12V battery charge
    • Red: left turn and brake lights
    • White: ground wire
  • Limited 1-year warranty


56000 CURT Fifth Wheel and Gooseneck OEM Extension Harness - 7-Way RV Blade Plug - 10' Long

Installation Details C56000 Installation instructions

California residents: click here


Customer Satisfaction Score:


Customer Reviews

Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 7-Pole Connector - 10' Long - C56000

Average Customer Rating:  4.8 out of 5 stars   (200 Customer Reviews)

Mount this 7-way, RV-style connector in your truck bed for quick, simple hookup of your 5th-wheel or gooseneck trailer. Custom harness plugs in-line with your existing factory wiring so that you can retain use of your vehicle's factory 7-pole.

by:
Ford Escape

Installation was very straight forward.
I
used some left over pieces of foam pipe insulation over the cable where it passed over the truck frame and th inner wheel well. I mounted the extended Seven Pin connector just forward of the wheel well just below the bed rail on the driver's side.
The umbilical from our 5th wheel reaches with enough slack to lay on the truck bed.
We picked up our Escape 5.0TA two weeks ago and drove about 3300 miles from WA to MI.
The plug was easy to plug in and unplug.
Overall a very nice product.

Ronald

4/12/2024

After 1 year still very satisfied with this product. Would buy again.

Etrailer Expert

Jerred H.

5/10/2024

@Ronald That's awesome! Thanks for the feedback!


by:

Worked great, I traded the vehicle that I installed the wiring adapter in tho. So it may be of use to someone else also.



by:

Initially worked great, but now it keeps losing connection to the camper. I had to plug the camper in to the 7 way on the bumper to get home. Everything would seem fine but then getting on the highway I'd get a warning message on the dash and lose lights/trailer brakes. Not something you want happening at 70mph.



by:
2016 Chevrolet Silverado 3500

Truly happy with this product and can't wait to go to work! etrailer sent me everything I requested and the installer had no problems. Everything was packed well in shipping with no problems.



by:
2016 Ford F-350 Super Duty

This product makes it so simple to add a Fifth wheel plug into the bed. Installation takes maybe 20-30 minutes. I installed mine on the column at the tailgate so it is out of the way (less likely to get damaged by other cargo). The only issue I experienced with install was that due to the small opening in that column (from under the vehicle), I had to remove the gray wire cover and then reinstall it after feeding the wire harness up into the column. (This was minor) Would definitely recommend this as it is simply "plug n play" with no cutting of wires or crimping needed.

Richard P.

8/31/2017

Product and location has worked perfectly and keeps on doing so. Great product!



by:

Product arrived overnight and I installed it upon arrival in order to be able to leave on a planned trip. Install was quick and easy and product was as advertised. I appreciated etrailer getting the order out immediately to me. Top rate company.



by:
2014 Ford F-250 Super Duty

Very pleased with etrailer.com. All product information and reviews help make decision very easy. Very quick delivery and installation instructions are very easy to follow. Purchased 5th wheel hitch and custom wiring extension for my 2014 F250.

Mike S.

6/9/2018

Thanks for the follow up. I’ve enjoyed the products ease of installation and use. I easily hook up my 5th wheel camper by myself and have had no issues. Great products!



by:
2021 Ram 2500

direct fit plug and play had no issues!



by:

Delivery was ahead of schedule. The product is top grade. I installed it myself which took all 45 minutes. Tested it on the trailer and everything worked perfectly.



by:
2016 Chevrolet Silverado 2500

The cord made the electrical part of installing my new fith wheel hitch very easy just plug in the connections and your done .

Kevin L.

10/23/2017

The products have worked flawlessly no problems and thank you for checking back with me its nice when a company cares about there costumers. Next time I need any trailer products I will definitely be contacting etrailer.



by:

Plug and play. Works great.



by:

The trailer wiring extension worked perfectly for my 2013 2500HD setup. It was easy to install and makes hooking up and trailering that much easier.



by:

Nice long wiring harness.



by:

Awesome product fit the truck just like it should and very easy to install keeps me from scratching the tailgate with a wire over the back of the truck easy to reach when hooking up trailer



by:

Working very well yet!



by:

Easy install and a great product. Used on 5th wheel rv trailer. No more wiring cord from trailer hanging over the end gate. Thanks!



by:

Went on in minutes



by:

Looks like an easy install good quality



by:

Customer service for product selection and order entry were excellent and focused on my interests and needs. The hitch, custom installation kit, and harness were shipped very quickly and arrived sooner than expected. Everything arrived in excellent condition. Assembly and installation instructions were very clear and specific, and I was able to assemble and install everything with no problems and in a very reasonable amount of time. Total cost was roughly half of what it would have been if I had purchased the products and had them installed by a dealer. I am very satisfied with my experience dealing with etrailer.com, and would highly recommend them to anyone shopping for towing products.

Peter C.

10/23/2017

Awesome. The hitch has worked great. Very, Very happy with the purchase,delivery, installation which I did myself, and performance of the product.Thanks again,Ill be sure to refer anyone who needs products you offer to you.



by:
2006 Ford F-250 and F-350 Super Duty

I'm a huge fan of completing wiring projects with no "hacking" into harnesses. This harness is plug and play. When I finished installing it, the underside of the truck looks like it came from the factory. Job done

Jim

3/4/2018

I havent thought about it for a year. I can give no higher praise for a product.it does its job very well.



by:
2019 Ram 2500

This is an easy install and seems well made. I probably didn’t need the 10’ long my truck called for but no problem zip tying up out of the way. Well pleased.



by:
2016 Ford F-350 Super Duty

I haven't installed it yet, however, I cut the inside bed wall in preparation for a spray-in bed liner before installing.
It looks just like the picture and description, arrived undamaged and ready for install. Great installation instructions!

Les

11/1/2017

Still using and I really like the hitch and other items I purchased a year ago. After installing the Curt fifth wheel hitch, Ive used it several times and I will be using it a bunch over rbe next several weeks. Easy to maintain and use.



by:

Worked perfect. Unfortunately 1 yr later at the bumper location (where the splitter is installed) I don't have reverse lights on my trailer. They still work from the new mount in the box, just not from the bumper location. It's possible it never worked from the beginning, as I didn't have a trailer with reverse light at the time, but I do now and they don't work... I understand I'm just outside of the 1yr warranty period too. My fault for not checking right away.



by:

This wiring harness made adding a plug in the bed of the truck for the gooseneck trailer a breeze. I didn’t really need the 10’ harness but I just looped and zip tied the excess. One year later and the plug still works great.



by:
2019 Dodge Ram Pickup

Quality product with simple plug and play installation.
My 2019 Ram 3500 does not have the fifth wheel prep package. This (and Curt fifth wheel hitch rails / brackets also purchased) made it easy.
Have used this product since 10/2019...no problems in wet or (AZ) dry.


25
200
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