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  1. Custom Fit Vehicle Wiring
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  3. Custom Fit
  4. Fifth Wheel and Gooseneck Wiring
  5. 7 Round - Blade
  6. 10 Feet Long
Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug

Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug

Item # HM42137
Our Price: $78.98
You Save: 27%
Custom Fit Vehicle Wiring

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Mount this 7-way, RV-style connector in your truck bed to simplify hookup of your 5th-wheel or gooseneck trailer. Harness plugs into existing wiring and retains use of factory 7-pole at the bumper. 90-Degree-angled connector fits into tight spaces. 1-800-940-8924 to order Hopkins custom fit vehicle wiring part number HM42137 or order online at Free expert support on all Hopkins products. Great prices and Fastest Shipping for Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug. Custom Fit Vehicle Wiring reviews from real customers.
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  • Reviews (128)
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Hopkins Custom Fit Vehicle Wiring - HM42137

  • Custom Fit
  • Fifth Wheel and Gooseneck Wiring
  • 7 Round - Blade
  • Hopkins
  • 10 Feet Long

Mount this 7-way, RV-style connector in your truck bed to simplify hookup of your 5th-wheel or gooseneck trailer. Harness plugs into existing wiring and retains use of factory 7-pole at the bumper. 90-Degree-angled connector fits into tight spaces.


  • Provides 7-way, blade-style connector in your truck bed for hassle-free hookup of 5th-wheel and gooseneck trailers
    • Connector head is designed with 90-degree angle so it fits into tight spaces in truck-bed side rails
    • Lid with oversize hinge opens 180 degrees for easy connection
  • Retains the use of the 7-pole connector at the rear of your truck
  • Installs quickly and easily - no cutting or splicing required
    • Plug T-connector into factory wiring and your vehicle's factory-installed 7-way connector
    • Run 10' long wiring harness from rear bumper to truck bed
  • Offers enhanced weatherproofing with internal seals, corrosion-resistant terminals and rubber-coated copper wiring
  • Constructed of extremely durable ABS plastic
  • Includes self-tapping screws, dielectric grease packet and nylon ties for installation


  • Harness length: 10'
  • Wire gauges:
    • Purple/green/yellow/brown: 16
    • Blue/red/white: 12
  • 3-Year limited warranty

This T-connector wiring harness uses your factory tow package to add a 7-way socket in your truck bed while also retaining the use of the 7-way at your vehicle's bumper. The harness plugs into the back of your 7-way at the bumper and also into your factory wiring. And it provides 10 feet of cord to run the second 7-way connector to your truck bed. Installing a second 7-way connector in your truck bed makes it easy to connect the 7-way plug from your fifth-wheel or gooseneck trailer.

42137 Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Way Blade Plug

This Product Fits The Following Vehicles

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug - HM42137

Average Customer Rating:  5.0 out of 5 stars   (128 Customer Reviews)

Mount this 7-way, RV-style connector in your truck bed to simplify hookup of your 5th-wheel or gooseneck trailer. Harness plugs into existing wiring and retains use of factory 7-pole at the bumper. 90-Degree-angled connector fits into tight spaces.

2006 Dodge Ram Pickup

Installed on my 2006 Dodge Ram 2500 in ten minutes. Works excellent! No more draping my wiring harness over my tailgate!


Works well. Defiantly better than installing a gooseneck under the bed hitch. You can swap the plate over to a fifth wheel plate with ease. 2 birds one stone. Defiantly recommend



Working great

2009 Dodge RAM 2500

Exactly what I needed. The Hopkins Endurance 5th Wheel 90-Degree Harness is truly plug 'n play. Once you decide on the truck bed location for the new 7-pole plug and drill the hole the rest is simply snap together and you're done. The new harness fit perfectly with the factory 7-pin connector and had plenty of length to allow for the new plug to be mounted conveniently in the truck bed wall. No more cable hanging out over the tailgate.

Steve M.


I have used the Hopkins Endurance 90-degree harness monthly over past year since installation. I have also used the factory bumper 7-pole plug as my towing needs required. Both connectors work every time indicating a solid fit and good contact between the factory 7-pin connector and the added Hopkins Endurance connector. Very pleased with both ease of installation and performance.


Perfect, easy install. Pu bed was wired for 5th wheel or gooseneck in l5 minutes.


Easy plug and play installation. So far so good.


Came on time perfect fit easy to install .

2006 Dodge Ram Pickup

Installation went great drill hole and plug everything in comes with enough wire to put virtually anywhere in the bed. I was very pleased with the quality of the connectors.


Easy to install, high quality good directions !

2007 Dodge Ram Pickup

This harness was a breeze to install. Simple unplug and plug back together, cannot be any easier. Harness was plenty long to locate the plugin anywhere you would choose. Factory style connectors worked perfect. Highly recommend this product and would absolutely buy again. Thanks etrailer for your quality products and wealth of application/installation info available!!!

Adam M.


Very well just as expected.


Worth every penny to keep everything in the bed when hooking to a fifth wheel or gooseneck. Very simple install with just needing a holesaw.


Didn’t end up needing so will return


Have not installed yet, looks like 30 minute job! Plug and play.


Very good quality. And easy to install.
Everything needed for installation provided.


Well made product. Heavy wiring. Easy to install. Worth the money!



No problems with product. Works like a charm & is easier to plug in and out than my older unit.


Definitely plug and play. No installation or use problems at all! The simple way to add 5th wheel wiring capability!

2006 Dodge Ram Pickup

Finally got the right part, my bad the first time, and the Hopkins wiring harness was in my 2006 Dodge Ram truck in less than 30 minutes. Most of your time will be spent drilling the hole in the side of the bed. I used a 2" hole saw vice the 2 & 1/8th (already had the 2" and didn't want to run out and buy another hole saw) and had no problems getting the harness through the hole. Hooked up the trailer and everything worked perfectly. There's plenty of harness, maybe too much, for any application in the truck bed. Great product!


High quality and good instructions. The manufacturer provides plenty of cable to put the additional connector virtually anywhere.

Bruce B.


Both continue to work fine!

2009 Dodge Ram Pickup

Wow what a fantastic experience! It first started when I called to verify I was buying the right 5th wheel wiring kit for my 2009 Dodge Ram 2500. Nicky K was the salesperson that helped me out, she took the time to verify my order and she placed the order for me at that point, I chose the two day delivery option and it arrived on time as she promised.
The endurance professional grade 5th wheel wiring kit part # 42137 was so easy that it took me only 45 minutes to install from start to finish, and most of that time was Running the wire from the bed location to the back of the truck where the factory 7 pin receiver is located. this kit is truly plug and play!! If I could do this in this amount of time and not have any problems then anyone can do it.
I would definitely recommend this company and this product to all my family and friends.


The wiring harness for my gooseneck 7 pole hitch on my Dodge is as advertised. The only problem is I looked under my truck it is not wired with a stock connector. I will have to cut and splice it anyway. Not a problem with the product but with my wiring.

2005 Dodge Ram Pickup

After using this plug adapter for a year I have been very satisfied. It was very easy to install, wiring plug was an exact fit. I use it for my fifth wheel travel trailer. I have not had any problems. Great product, thanks.


Ordered part and it was picked, packaged and shipped same day and arrived when said. I would order from you again. I ordered the 5th wheel harness for bed of truck. Just unplug one wire harness and plug in the other, easy and fast.

2001 Dodge Ram Pickup

I originally had ordered a different product but it was back ordered a month which I was ok with. After I placed the order, I received an email stating they had another conector that was basically identical that was in stock and if I wanted to switch to that one, I could call in and switch. So, I called in and they changed my order to that in-stock plug and it was here within a week! Awesome and easy customer service. It was also really easy to truck.

As for installation, it went flawless and I was done in under an hour. Hooked it up to one of my trailers and everything works perfect (including trailer brakes). Very happy with the whole purchasing/installing experience!


Super easy install. Only needed about half the length of the wiring harness it comes with. Forget looking all over for a 2 1/8" hole saw. A 2" will do the trick. (The trailer video says 1 1/8", but that needs to be corrected). This harness is well worth the money.


BW make a fine product

2006 Dodge Ram Pickup

The hitch was better than I thought it would be. Installation was easy with the enclosed instruction sheets. The Quality of the hitch assy. is great. I highly recommend this hitch.
The wiring harness worked great and was easy to install.

Show More Reviews

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

  • How to Add an Additional 7-Way Connector in the Truck Bed on 2006 Dodge Ram 2500 with Factory 7-Way
    You will need the Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug Item # HM42137, for your 2006 Dodge Ram 2500. This harness will fit your 2006 Dodge Ram 2500 with a factory installed 7-Way connector. It will plug in between the factory wiring harness and the factory 7-Way and give you an extra 7-Way in the truck bed, but still retain the use of the factory 7-Way on the bumper.
    view full answer...
  • 7-Way Kit for Truck Bed of 2005 Ram 2500 for Fifth Wheel Towing
    We have the Hopkins 5th Wheel 7-way kit part # HM42137 which fits your 2005 Ram 2500 and will give you a 7-way you can mount up in the truck bed. This allows you to keep the 7-way at the rear of the truck as well. It installs by plugging inline with the 7-way you have now and then would get installed where you would like in the truck bed.
    view full answer...
  • Troubleshooting Brake Controller that Does Not Work at Trailer Connector
    If the brake output is active at the back of the controller but then not active at the 7-way connector that would indicate you have a short on that circuit somewhere between the two. It could be as simple as corrosion on the pins of the 7-way or even at the back but if not you'd have to trace the wiring to find the short and fix as needed. I attached a help article on troubleshooting brake controller installs for you to check out as well.
    view full answer...
  • Will In Bed 5th Wheel/Gooseneck Trailer Wiring Harness Fit a 2004 Dodge Ram 2500
    The Valley in bed wiring harness, # HM42137 will fit your Dodge Ram 2500 series trucs. The truck will need to have a factory 7-Way trailer connector for the harness to install in line with the factory wiring. I have included a link to a video that shows a typical installation for you.
    view full answer...
  • Will The Hopkins Fifth Wheel Wiring Harness for a 2008 Dodge 3500 Keep the 7-Way at the Bumper
    The Hopkins 5th wheel wiring harness # HM42137 acts as a T-connector. It will provide a 7-way trailer connector in the bed of your truck while retaining the one at the back too. This fits all 2008 Dodge trucks with factory installed 7-way connectors.
    view full answer...
  • In Bed Trailer Wiring to Tow Gooseneck Trailer with 2007 Dodge Ram 1500
    We have exactly what you need with part # HM42137. It plugs inline with your 2007 Dodge Ram's factory 7-way so you keep the original connector and can add thi one into your truck's bed to hook up your gooseneck trailer.
    view full answer...
  • Installing Truck Bed Trailer Connector on 2008 Dodge Ram Truck
    Actually, the # HM42137 that you looked at is exactly what you need. This harness will plug inline at the connection where the 7-way on your back bumper plugs into the truck's tow package harness, right behind the connector itself as shown in the video I've linked for you. Once installed, both the trailer connector in the bed and the one on the bumper will be operational. It's a very simple install that'll take less than an hour.
    view full answer...
  • Can 7-Way Wiring be Used to Power Headache Rack Lighting Functions
    The problem with using 7-way wiring for a headache rack is that there isn't a dedicated stoplight circuit so if the rack has a third brake light you won't find the correct circuit at this harness. The turn signals, running lights, and reverse lights are present though with the # HM42137. I attached a diagram that shows where you'll find them.
    view full answer...
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  • Installing In-Bed 7-Way on a 2005 Dodge Ram 2500 and Max Weight Rating for Towing 5th Wheel Trailer
    The Hopkins 5th Wheel/Gooseneck 90-Degree Wiring Harness w/ 7-Pole Plug # HM42137is an excellent option for your 2005 Dodge Ram 2500 and it installs by teeing into your factory wiring and then the wiring harness will be routed up to the side of your bed and you'll drill a hole to mount the 7-Way plug. Attached is an installation video on a 2005 Dodge Ram that you can check out. As far as weight capacity goes it looks like the max towing weight a 2005 Dodge Ram 2500 with the Cummins can...
    view full answer...
  • Which Fifth Wheel or Gooseneck Harness Should be Used for 2010 Dodge Ram 3500
    For your 2010 Dodge Ram 3500, you would need 5th Wheel and Gooseneck 90-Degree Wiring Harness with 7-Pole Connector, # HM42137 The 90 degree angle reduces the amount of space the truck bed connector needs making installation easier.
    view full answer...
  • Why Does the Hopkins 5th Wheel Wiring Connector have 10 Pins but only 7 are Used
    As long as you are installing the 5th Wheel/Gooseneck 90-Degree Wiring Harness # HM42137 on one of the vehicles that is a confirmed fit for you should be fine. To see if this is the correct product for you scroll down on the product page to see if this is confirmed fit for your vehicle. The reason your factory connector has more female pins than the red side of the # HM42137 has male pins is because there are only 7 circuits that need to be run to your 7-way so only 7 pins need to be used...
    view full answer...
  • Recommended In-Bed 7-Way Trailer Wiring Harness for a 2005 Dodge Ram 3500
    Absolutely, the Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness part # HM42137 will give you a 7-way trailer connection point in the bed of your 2005 Dodge Ram 3500 for use with gooseneck/5th wheel trailers and still retain the use of the 7-way trailer connector on your bumper. I have attached an install video of the above harness for you as well.
    view full answer...
  • Trailer Running Lights Come On when Horse Trailer is Connected to Shore Power or Using Battery
    It sounds like the trailer running light circuit is somehow connected with the 110/12 volt transfer switch which also probably is able to charge the trailer battery. You can follow the running light wire from the front of the trailer and see where all it goes to determine if that is what is going on. There could also be some sort of back feed short. Make sure that the trailer connectors are clean and free of corrosion inside and out and that all of the grounds, including the ones for...
    view full answer...
  • Replacement 7-Way Recommendation for a 2006 Dodge Ram
    I have a solution for you, but the part # HM42137 is not it. For a replacement 7-way for your truck you would need the part # HM42190. This will plug in to a square connector like the 7-way of your truck currently does to provide you with a new 7-way.
    view full answer...
  • Recommended 5th Wheel/Gooseneck 90 Degree Wiring Harness For A 2008 Dodge Ram Pickup
    When it comes to installing a 5th Wheel/Gooseneck 90 Degree wiring harness I recommend The Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug # HM42137. This harness is confirmed to fit your 2008 Dodge Ram Pickup. Using this harness provides a 7-way blade style connector in your truck bed for a hassle-free hookup of the 5th wheel and gooseneck trailers. The harness length is 10 foot. The wire gauges are below: Purple/Green/Yellow/Brown - 16 Gauge Blue/Red/White...
    view full answer...
  • 7-Way Wiring Recommendation for Fifth Wheel 7-Way in the Bed of 2001 Dodge Ram 2500
    Looks like somebody used quick splices to wire in the 7-way on your 2001 Dodge Ram and then when they removed the 7-way they just cut the wires leading to them. Thank you for the picture though as that helps me understand you setup very easily. Since it sounds like you are trying to install a second 7-way in the truck bed of your truck the easiest solution would be the part # HM42137 that would install inline with the factory 7-way wiring harness.
    view full answer...
  • Installing 7-Way Trailer Connector in Bed of 2006 Dodge Ram
    Hopkins offers a T-Connector type set up, part # HM42137 that would plug inline with the existing 7-way on your bumper and provide a 7-way in your truck bed. The wiring harness is 8 feet long, but any existing slack can be taken up and bundled up under the vehicle with zip ties. Using the T-Type connector will allow a 7-way to remain at the rear bumper while adding one to the truck bed, which you would not have if you simply relocated the existing 7-way to the truck bed. The HM42190 you...
    view full answer...
  • Gooseneck/5th Wheel Wiring Harness Recommendation for a 2007 Dodge Ram 2500
    There is a fifth-wheel and gooseneck wiring harness for your 2007 Dodge Ram 2500 Pickup. You will want a Hopkins fifth-wheel and gooseneck wiring harness, part # HM42137, for your Ram. I have attached an installation video for this product on a very similar truck for you to check out. You may also be interested in purchasing some Dielectric Grease for Electrical Connectors, 2 oz., part # 11755. It is always a good idea to use dialectic grease when making electrical connections, to prevent...
    view full answer...
  • Will the 5th Wheel/Gooseneck 90-Degree Wiring Harness # HM42137 Fit a 2004 Dodge Ram 1500
    The 5th Wheel and Gooseneck in bed wiring harness, # HM42137, will fit a 2004 Dodge Ram 1500 provided that the truck came with a factory 7-Way trailer wiring harness. This harness plugs in line with the factory harness. I have included a link to a video that shows a typical installation for you. Additional models that this harness will fit are listed near the bottom of the product page. If it is not a factory 7-Way then you will need to use an extension type of harness, # 20027, that plugs...
    view full answer...
  • Trailer Wiring Harness for an In-Bed Camper for a 2002 Dodge Ram 2500
    Trailer connector # 20135 is meant as a replacement for the factory 7-Way trailer connector on a 2002 Dodge Ram. If your truck did not come with a factory 7-Way then this connector will not work. If it does have a factory 7-Way then I think I have a better option for you since you need the connection to be more at the front of the bed for the camper. You can use a 5th wheel/gooseneck harness and connector, # HM42137. This will plug in line with the factory 7-Way wiring. Normally the connector...
    view full answer...
  • Can Second In-Bed Fifth Wheel 7-Way Harness Be Installed On 2002 Dodge 3500 Truck
    Although I have not heard of someone installing a second 7-way connector in the bed of their truck, it could be done. I strongly recommend making sure that you use dielectric grease like part # 11755 to make sure you are receiving the best chance for the proper amount of current with your wiring. You will want to make sure you secure the wiring so that it has no chance of separating under the truck. As I said I have not heard anyone say they were installing an additional connector so...
    view full answer...
  • Looking to Add Plug and Play 7-Way Wiring Harness to Bed of 2007 Dodge Ram 3500
    As long as your 2007 Dodge Ram Pickup is equipped with a factory 7-way, you can use the Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness, # HM42137. This harness will plug into the existing wiring to give you a 7-way in the bed and also retain the use of the 7-way at the back of your truck. I have included a video for you. The 7-Way Pre-Wired Car Connector, # 20023, is not a plug and play option. Wiring would be required.
    view full answer...
  • Is There a Gooseneck/5th Wheel Wiring Harness Available with a Shorter Length of Wire
    The shortest gooseneck wiring harness we offer is the Draw-Tite 5th Wheel and Gooseneck Wiring Harness with 7-Pole for Dodge with Factory Tow Package # 20111. This wiring harness is 7 feet long and will install behind the factory 7-Way on your 2007 Dodge Ram Pickup. The Hopkins Endurance 5th Wheel and Gooseneck Wiring Harness # HM42137 that you referenced is a great option, however it does not come in a length shorter than 10 feet. Typically the extra wire from the harness is bundled...
    view full answer...
  • 7-Way Trailer Wiring Harness to Install in Bed of 2017 Ram 2500
    For a 7-way to install in the bed of your truck up near the front you'd want the Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug # 41157 which is as confirmed fit and would work well. We had the chance to install this in a 2017 Ram 2500 just like yours as well. See install video below.
    view full answer...
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Info for this part was:

Employee Frances L
Edited by:
Frances L
Employee Tyler C
Written by:
Tyler C
Employee Jeff D
Installed by:
Jeff D
Employee Jameson C
Expert Research:
Jameson C
Employee Jeffrey L
Expert Research:
Jeffrey L
Employee Joshua S
Video Edited:
Joshua S
Employee Chris R
Video Edited:
Chris R
Employee Laura H
Updated by:
Laura H
Employee Alexander C
Updated by:
Alexander C

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