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Hopkins Endurance 4-Way Flat Trailer Wiring Harness - 20' Long
(58 reviews)
Price: $25.97
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Hopkins Endurance 4-Way Flat Trailer Wiring Harness - 20' Long
Part Number: HM48240
In Stock
$25.97
Retail:$28.89
You Save: 10%
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- Reviews (58)
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Hopkins Trailer Wiring - HM48240
Highlights
- Easy Trailer Rewire: 20' wishbone harness splits running lights to each side for simple routing.
- Reliable Ground: 36" white wire with ring terminal secures to clean metal for solid connection.
- Clear Wire ID: Color-coded and labeled every few inches so you know each function at a glance.
- Durable Build: 18-gauge lighting wires and 16-gauge ground stand up to regular towing use.
- Quick Disconnect: Ergonomic grip on 4-flat plug makes connecting and unplugging effortless.
Features to know about
Simplifies Trailer Rewiring: 20-Foot Harness with Wishbone Design
Running lights don’t have to be a headache to wire. This 20-foot Hopkins Endurance 4-Way Flat Trailer Wiring Harness uses a wishbone layout, splitting the brown running-light wire into two — one for each side. That means no need to splice or tee wires across the trailer frame. It’s built for a clean, simple install when you’re replacing or upgrading your old wiring.
Reliable Connection for Key Lighting Functions: 4-Flat Plug and Lead
The 4-flat connector gives you running lights, left and right turn signals, and brake lights through color-coded wires that are clearly marked every few inches. The green wire handles right turn and brake, yellow covers left turn and brake, and the brown wires power the tail lights. A 36-inch white ground wire with a ring terminal keeps everything solidly grounded once attached to bare metal.
Built Strong for Everyday Use: 18-Gauge Lighting Wires and 16-Gauge Ground
Each lighting function runs on stranded 18-gauge copper wire, while the dedicated ground is a thicker 16-gauge for dependable current flow. The insulation measures between 10 and 12 gauge with the jacket on, offering extra toughness against wear and corrosion. It’s a simple, long-lasting setup that holds up to regular towing.
Easy to Handle When Hooking Up: Ergonomic Grip Connector
Pulling trailer plugs apart can be tough when they’re tight or wet. The Hopkins Endurance connector has an ergonomic grip molded into the plug, so you can disconnect it easily without twisting or yanking on the wires. It’s a small feature that makes hitching and unhitching smoother every time you tow.
Specs
Electrical Specifications
- Wire Gauge (lighting functions): 18 gauge stranded wire
- Wire Gauge (ground wire): 16 gauge
- Harness Length: 20'
- Construction Type: Wishbone harness (dual running light wires, one for each side of trailer)
- Left-Side Tail Light Wire: Bundled with yellow left turn/brake wire
- Right-Side Tail Light Wire: Bundled with green right turn/brake wire
- Ground Wire: 36" long white wire with ring terminal
- Wire Markings: Each wire marked every 6–8 inches with function and color-coded stripe
- Green Striped Wire: Right turn
- Brown Striped Wire: Taillights
- Yellow Striped Wire: Left turn
48240 Hopkins Endurance 4-Wire Flat Y-Harness
Ratings & Reviews
4.8
58 reviews
by:
Barry
04/14/2020
Very happy with every aspect of my order. Received product and quality appears to be outstanding. I’m especially impressed at the instructions made available to install the wiring harness, written with the product and link for video. All bases covered and follow up to make sure all goes well. Am confident of their assistance should I need it.
by:
Classic RV Restoration
11/04/2016
I used this harness to rewire a 10ft vintage RV. There was plenty of length to reach the rear lights. I used Scotch Locks to tap into the wiring for the side running lights. Very good product.
by:
Pete
06/11/2013
Before I start I want you all to know I am not good at anything with wires or water, period.
I had an old 4x8 trailer that needed to be re-wired. I was not looking forward to screwing it up which was inevitable If I touched it. But, I need the trailer for the July 4th weekend so by chance I ran across your site. I found the video on how-to rewire a trailer. Though you made it look easy *I* would be attempting this! Okay, the project took a bit of time since I questioned everything twice (about an hour) but I have to say, IT WAS NO PROBLEM re-wiring the trailer. The 4-way trailer harness is much better than the harness I had on it and the whole project was actually fun to do (and I hate this type of stuff). I love the quality and really love the connector 'cap', even though the trailer is garage kept.
Thanks for the products and the video assistance, it was easy because of you!
I had an old 4x8 trailer that needed to be re-wired. I was not looking forward to screwing it up which was inevitable If I touched it. But, I need the trailer for the July 4th weekend so by chance I ran across your site. I found the video on how-to rewire a trailer. Though you made it look easy *I* would be attempting this! Okay, the project took a bit of time since I questioned everything twice (about an hour) but I have to say, IT WAS NO PROBLEM re-wiring the trailer. The 4-way trailer harness is much better than the harness I had on it and the whole project was actually fun to do (and I hate this type of stuff). I love the quality and really love the connector 'cap', even though the trailer is garage kept.
Thanks for the products and the video assistance, it was easy because of you!
by:
Fernando G
07/31/2017
Had to replace my electrical wiring for my boat trailer. Mice had chewed the previous wiring. etrailer wiring kit was delivered on time per all expectation, great price. Installed effortlessly, this time I closed off the entry points for rodents. Thank you etrailer
by:
Casey
10/26/2011
the only thing i dont like about it is the thin insulator around the wires. wires on trailers are constantly rubbing on something, and this harness is lacking good insulation. it looks similar to cheap speaker wire. i bought a roll of split loom to put the wire in. plug appears to be nice and sturdy. iv only plugged it in once to make sure might lights work....but it looks like it should be fine. 4 out of 5 stars.
by:
Fred S.
03/10/2014
This is an excellent alternative to purchasing the 4 way connector alone. All leads are built into the connector, which means you don't have deal with that part of the installation process. The ground wire has a good length to it, with the screw end circle easily fastened to the trailer. The length of the other wiring allows for you to completely rewire a small trailer like the one that I've replaced. I recommend this product if you're looking for a hassle free replacement or upgrade of your existing trailer wiring system.
by:
wade
05/13/2015
I am really impressed with etrailer. i got my wiring harness in the mail to day and had the trailer wired up in about an hour. love the ease of wiring the trailer with the two sets of wires.
by:
Mark
01/07/2019
Used this wiring harness to replace the existing one on my utility trailer. So nice to have reliable lights now.
by:
Ron S Kansas
01/11/2011
Wiring harness is nicely assembled, with an anti abrasion sleeve on the end, nie weather cap for the connector, grounding lug is already attached. It even includes attachment screw for grounding lug, and terminal grease to help fight corrosion. My dog ate the head off of my old harness and it was cheaper to replace the entire harness than to splice and curse and add assorted parts. This harness is COMPLETE, and will really do the trick. Quick delivery, reliable people..Etrailer.com.
by:
Bob V.
07/31/2013
Great value and the communication and shipping time couldn't have been better.Can't wait to wire up the lights for the hitch mounted rack for my Honda F6B.
Thanks
Thanks
by:
Robert
02/12/2013
Product looks to be top quality and was delivered to me with out issue. I will be installing it on a utility trailer I have that the original wiring on is starting to malfunction due to wear. This product interested me because of the durable wrapping and split leads for each side. Thanks and I will be using etrailer.com for any of my future trailer accessory needs.
by:
Ray C.
07/20/2017
Got the tires, wheels, lights, and wiring kit to rebuild an old utility trailer. The website has a wealth of info to help find exactly what was needed. Michelle S. was very helpful (and friendly!) in resolving a delivery question.
by:
Dan R. Oregon
05/23/2011
taste of trailer plugs.
Its exactly as shown in photo.
Quick delivery.....Thanks again etrailer.com
Its exactly as shown in photo.
Quick delivery.....Thanks again etrailer.com
by:
John W
09/23/2020
Very solid product! It gives me confidence it will last a long time. I would have preferred to be able choose a coiled harness of the same gauge wiring but wasn't able to find one. Instead, I took this one and adding some flexible tubing to allow it to stretch when turning, and it works well enough
by:
Robert
09/17/2019
Excellent product but found it to be too short for utility trailer I’m rewiring and had to order a different harness that is longer
by:
Jeff
06/02/2016
Fantastic product. Easy to install. The 4 pronged connector is well made and is not flimsy like other connectors.
by:
Keith S
02/22/2017
Great product for rewiring an old trailer. Got it installed in about an hour and I have lights again. Thanks.
by:
Ted Beard
02/27/2012
service was top notch.
items were not only shipped the same day, they were shipped immediatelly following the order, and arrived a few days later.
thank you for the great service i will probably use the website again for other trailer parts.
items were not only shipped the same day, they were shipped immediatelly following the order, and arrived a few days later.
thank you for the great service i will probably use the website again for other trailer parts.
by:
Greg
08/15/2019
Etrailer is awesome! They have everything you Can imagine and the shipping is super fast! Thanks for everything!
by:
John McIntosh
07/29/2015
Assembled today, perfect. Everything worked as planned. I am SO happy with etrailer. Everything I have purchased from them has been above expectations and customer service has been awesome. Thank You!
by:
John M
06/05/2016
Products were as advertised and delivered promptly what more could I ask for great product , price and service.i will continue to use etrailer as my need arise.
by:
Steve C
12/30/2016
This harness was a great solution for my trailer project. Has held up very well.
by:
william
04/09/2013
this is an excellent product. it has solved all my problems with spliced wires on my trailer.also very easy to install in the existing hangers
by:
Zvi F.
01/06/2016
Easy to install, got it right away, like all the other times with eTrailer.
by:
Chad
04/27/2012
with plenty of insulation.
Shipping was extremely fast. Will be ordering from these guys again.
Shipping was extremely fast. Will be ordering from these guys again.
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view full answer... - What Guage Wire Does Hopkins 4-Way Trailer Wiring Harness UseThe Hopkins 4-Way flat Trailer Wiring Harness uses 18 awg stranded wire for the right turn, left turn and tail light functions. The ground wire is 16 awg. Hopkins does a really nice job with this harness, they have each of the wires marked about every six to eight inches with the function of each of the wires. Each of the wires also has the color coded stripe that correlates to the function. The green striped wire is for your right turn, the brown striped wire is taillights and the yellow...
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Barry
4/14/2021
Excellent quality product, works like a champ , no signs of corrosion in spite of outdoor storage