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Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End - Ergonomic Design

Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End - Ergonomic Design

Item # HM48030
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This heavy-duty 4-way flat trailer connector socket mounts on the vehicle. A weatherproof, insulated lid covers the terminals and the large grip makes connecting the plugs quick and easy. Lowest Prices for the best trailer wiring from Hopkins. Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End - Ergonomic Design part number HM48030 can be ordered online at or call 1-636-306-4830 for expert service.
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  • Reviews (37)
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Hopkins Trailer Wiring - HM48030

  • Trailer Connectors
  • Vehicle End Connector
  • 4 Flat
  • Plug and Lead
  • 0 - 5 Feet Long
  • Hopkins

This heavy-duty 4-way flat trailer connector socket mounts on the vehicle. A weatherproof, insulated lid covers the terminals and the large grip makes connecting the plugs quick and easy.


  • Easy pull, over-sized grip - makes connecting/disconnecting quick and easy
  • Heavy-duty housing with dust cover protects the terminals
    • Housing also has mounting holes to connect to brackets or bumper
  • Terminal grease packet included
  • 4-way flat socket (vehicle side)
  • Works with all 4-way flat connectors


  • Wires: 48" Long
  • Pigtail leads with ring terminal installed on ground wire
  • Wire Configuration:
    • Yellow - left turn and brake
    • Green - right turn and brake
    • Brown - tail
    • White - ground

48030 Hopkins Enurance 4-Wire Flat Trailer Connector - Vehicle Side

California residents: click here

Video of Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End - Ergonomic Design

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Hopkins Wiring - Trailer Connectors - HM48030 Review

Today we're going to be taking a look at part number HM48030. This is the Hopkins Endurance 4-Way Flat Trailer Connector Socket for the vehicle end. It's going to feature an easy pull oversize grip. It's going to make connecting and disconnecting quick and easy. It's got the heavy duty housing with the included dust cover that's already pre-attached to the housing. That's designed to go over the connection points and protect them from the elements when your connector is not in use. The housing is also going to feature a couple mount holes.

That way you can connect this to the bracket or to the bumper of the vehicle. It's going to include a terminal grease packet and a self-tapping screw for a ground connection. Both of those are included. The terminal grease, we always recommend to use that on all electrical connections. That's going to help prevent any type of corrosion from settling in and causing any type of damage to the connections themselves. This is a 4-way flat socket for the vehicle side.

It's going to work with all 4-way flat connectors, a universal system. It's going to have the protective sleeve that goes from the back of the connector. Looks to be about 12 inches deep here on the wiring. That's going to prevent or insulate the wires from any type of wear or tear or damage. It's also going to help protect the wires at the plug from the weather.

The wires are going to measure 48 inches in total length. It's going to feature the pigtail leads. One wire is going to have your ring terminal attached to it. That's going to be for your ground connection. That's the black wire with the white stripe.

The black wire with the green stripe is going to be for your right turn and brake signal. The black wire with the yellow stripe is for left turn and brake, and then the black wire with the brown stripe is going to be for your tail lights. That's going to do it for today's review of part number HM48030. Hopkins Endurance 4-Way Flat Trailer Connector Socket for the vehicle end. .

Customer Reviews

Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End - Ergonomic Design - HM48030

Average Customer Rating:  4.9 out of 5 stars   (37 Customer Reviews)

This heavy-duty 4-way flat trailer connector socket mounts on the vehicle. A weatherproof, insulated lid covers the terminals and the large grip makes connecting the plugs quick and easy.


It worked just fine and I sold the trailer after repairing the harness.


Hitch for 2018 EcoSport SES. Easy to install and looks good. Wire end with cover also looks good


Very satisfied


Product performed as expected and arrived quickly. Thank you.


Product was awesome. My last two connectors have corroded so bad within a year that I constantly was having to take a wire brush and clean off the pins to get good contact. I'm waiting to see what the environmental cap does to eliminate me having to do this. Also bought the vehicle side. Would highly recommend this to anybody with a trailer hook-up. Only thing I would suggest is to make sure anybody purchasing also buys the splices since none come with the product. All in all, a great buy. Thanks!

Using dielectric grease in the trailer connectors can also help reduce corrosion of the contacts.
-- Etrailer Expert Patrick B - 07/31/2013


Plenty of options and easy process

Still working as it should
James - 09/12/2021


Well made and delivered exactly as ordered. I used it in a custom wiring harness for a tow dolly. I wanted to provide a connection for magnetic based lights to place on the towed vehicle. It was perfect for my application.


Fast Delivery and exactly want I ordere d!


Did lot of searches for an item like this and found it only on etrailer.
Ordering was easy, communication was excellent and shipped
promptly. Item looks to be well made and I can install it by drilling only
one hole. Exactly what I needed for my application.


Ordered a bunch of stuff for hooking up a towed. Everything arrived as ordered and quick shipping. Everything fit the application without much trouble. Communication from etrailer was excellent. I would purchase from etrailer again.


Product was top quality. Exactly how it is described on the web site. fantastic company to deal with. Great prices and great service.


I like the quality and style of this pr oduct.


Used this to wire a car towed behind an RV. Easy to fasten the plug to car with the mounting holes


Works like it should. Its installed on my '63 Land Rover that has an unusual (for North America) plug. It connects to my '53 Canadian Bantam army trailer like a dream.

Thanks guys!


All items were received as described, packing was very protective and I ordered standard shipping but was upgraded free of charge. Great place for purchases for all your towing needs.


The vehicle-side trailer was received in good time, nicely packaged, and it’s exactly what I ordered. Thank you so much!


Buy from e trailer all the time great price and ships right away!


Always quality products and great customer service!


Wired up quick. Great quality. Extra heavy boot to protect pins.


Nice little connector just what I wante d!


received in good order. thank you

Very satisfied with the product.
James - 06/22/2020


Heavy duty, quality with protective cap. Much better than OEM equipment.


Parts worked as expected, more robust rubber connection than others.


Fast delivery as always.


Product exactly as described. Appears to be of good quality.

Show More Reviews

See what our Experts say about this Hopkins Trailer Wiring

  • What is the Hole Spacing for Hopkins Endurance 4-Way Flat Trailer Connector Socket HM48030
    The holes on the 4-Way connector of # HM48030 are space 1-5/8 inches apart on center. None of the brackets are a perfect match.
    view full answer...
  • Replacement 4-Way Recommendation for Vehicle with 5 Wires Ran to 4-Way
    For a very rugged replacement 4-way for you to use on your vehicle we have the part # HM48030 which would work well. Chances are you have two wires ran to the running light circuit of the 4-way. What you can do is run those wires together and then run them to the one running light wire of the # HM48030 and you would be just fine.
    view full answer...
  • Replacement 4-Way Connector Recommendation for Trailer To Allow Ford Ranger to Tow it
    You are going to have to rewire the connector that's on your trailer. What you have is not a standard trailer wiring connector so going to a standard 4-way like the # HM48030 would make life much easier.
    view full answer...
  • No Tail Lights On Boat Trailer When Parking or Headlights of 1995 Ford Truck Are On
    It sounds like you have a common ground problem. When the headlights are on, the highest amperage draw is placed on the wiring system and if you have a bad or loose ground, you will have problems with lights. You will want to inspect to make sure all the light assemblies have a good ground connection to a clean, rust and paint-free metal surface. You will also want to make sure the trailer and vehicle side connector have a good ground connection. I would recommend unbolting the ground...
    view full answer...
  • Correct Vehicle and Trailer Side Hopkins Endurance 4-Way Flat Trailer Connector
    The Hopkins Endurance 4-Way Flat Trailer Connector part # HM48110 is a trailer side connector which is designed to be installed on the towable. If you're instead looking for the vehicle side which is designed to be installed on the tow vehicle then you will need the Hopkins Endurance 4-Way Flat Trailer Connector part # HM48030. These harnesses both require splicing whether you are just replacing a trailer connector or wiring one for the first time.
    view full answer...
  • How to Access 5th Wheel Taillight Wiring for Installing Wiring Harness
    Usually it will be necessary to remove interior trim panels to access the taillight wiring of a 5th wheel. If your particular trailer's taillights offer access from the exterior then you'll have an easier time getting to the wiring to allow you to test it for function. It is worth contacting the trailer maker with your VIN to see if they can offer you guidance for accessing the wiring. You will want to use a tester like # 40376 to confirm the signal carrier on each RV taillight wire so...
    view full answer...
  • Parts Needed to Replace 7-Way of Motorcycle Trailer with 4-Way
    To replace the 7-way of your trailer with a 4-way basically just requires you to install a 4-way like the # HM48030 in place of the 7-way. You really only need trailer lighting functions so what you would want to do is use a jumper wire to put 12 volts from a vehicle battery onto each of the wires of the trailer's wiring to determine which wires you need. The 4-way has white for ground, brown for running lights, yellow for left turn/stop, and green for right/turn stop. If you find that...
    view full answer...
  • Changing Trailer From 6-Way to 4-Way
    If you wanted to change the wiring on your trailer to match the 4-Flat on your van, that would be the simplest solution. All you would need to do is cut off the 6-Way, use a circuit tester # 40376 on the vehicle side to make sure you know each of the wire's functions and then install them in a 4-Way # HM48030. Keep in mind you will also need to use a separate 12V power source such as a battery in order to test the trailer's functions.
    view full answer...
  • How Come this 6 Way Square Adapter # 30104 Will Not Work on My 1983 Coleman Pop Up
    The reason you are not getting the lights to work is that this Adapter 4 Way Flat to 6 Way Square for Jayco, part # 30104, is because this adapter is wired to only work on Jayco trailers, and is not wired to work on your Coleman Pop up. Although we can not sell you an adapter that would work on your Coleman trailer because of propriety issues with Coleman, there is a way you could get your trailer lights to function properly. You will need to connect the # 30104 to your vehicle and then...
    view full answer...
  • My Trailer Lights are Very Dim what Could be the Issue
    That's a tough one! You have already done everything I would recommend on the trailers side. It is definitely a ground issue and the only thing you have left is the plug end on your truck or the ground wire from the plug to the trucks frame. Check the ground connection to the frame of your 2005 Ford Ranger first then if that doesn't get it done put a new 4-way flat on the Ranger like the Hopkins Endurance 4-Way Flat Trailer Connector Socket part # HM48030. The ground wire on the trailer...
    view full answer...
  • 4-Way for Vehicle Side to Match Wesbar Wishbone 4-Way # 002402
    Since the Wesbar wishbone 4-way part # 002402 is a standard 4-way all you'd need is something like the part # HM48030.
    view full answer...
  • Trailer Wiring Harness for a 2012 Kia Sorento
    Your 2012 Kia Sorento has a separate wiring system. This means that the brake lights and turn signals are on different circuits/bulbs. Trailers on the other hand have a combined system with the turn signals and brake lights on the same circuit/bulb. So you would not be able to just wire in a vehicle side 4-Way directly to the lights on the Sorento because you would either have brake lights or turn signals but not both. You will need the proper harness that includes a converter for your...
    view full answer...
  • Troubleshooting Running Lights Circuit on Factory 4-Pole Wiring on 2011 Ford Ranger
    The best way to evaluate the operation of the factory 4-pole wiring harness on your 2011 Ford Ranger is to use a circuit tester like # 40376 but there are also checks you can do without a tester. It is possible that you may have just a corrosion problem on your 4-pole and this is easy to check. Inspect the metal contact surfaces for any signs of even slight greenish or whitish discoloration. Pay particular attention to the pin for the brown (tail light) wire. Clean the contacts as necessary. Another...
    view full answer...
  • Vehicle Side 4-Way to Match Wesbar 4-Way part # W787268
    While Wesbar doesn't have an exact match for the trailer side 4-way part # W787268 we do have similar 4-ways like the part # HM48030 from Hopkins that would work great.
    view full answer...
  • 4-way Options for use With a Tow Ready Mounting Bracket
    The Hopkins 4-way # HM48030 that you referenced is a great 4-way, but like you noticed, it is much larger than most 4-ways so it would not fit through the Mounting Bracket 4-Pole Flat # 18144 that you have. You basically have two choices at this point. You can either buy a different 4-way that will fit through the hole of the # 18144. Or you could cut off your # HM48030 and then run the wires through the front of the # 18144 and then reconnect the wires to the 4-way wiring of your vehicle. Check...
    view full answer...
  • Troubleshooting no Power to Trailer Turn Signals
    If your trailer turn signals are not working there are a number of different reasons and there are some troubleshooting steps you can take to determine the specific problem. The first thing to do is take a look at your owner's manual to locate where any trailer fuses or relays and ensure they are all there and in working order. If they are, since you tested the plug on your 2001 Chevy and found no signal at the turn signals, check your connector for corrosion, which can be green or white...
    view full answer...
  • Making 4-Way to 5-Way Round Adapter
    We do not carry that specific adapter, but we do carry the parts you need to make one. You can use the Pollak 5-Pole, Round Pin Trailer Wiring Connector - Chrome - Trailer End # PK11502 along with the Hopkins Endurance 4-Way Flat Trailer Connector Socket - Trailer End # HM48030.
    view full answer...
  • Adapter for 5-Pin Round Trailer Connection to 4-Way Trailer Connection
    We do not carry that adapter, but we do carry the parts you need to make one. You can use the Pollak 5-Pole, Round Pin Trailer Wiring Connector - Chrome - Trailer End # PK11501 along with the Hopkins Endurance 4-Way Flat Trailer Connector Socket - Vehicle End # HM48030.
    view full answer...
  • How to Stop an LED Accessory from Tripping the Towing Sensor on a 2019 Ford F-350
    So this will sound odd, but sometimes these kinds of accessories that plug into the vehicle's trailer plugs can trick them into thinking a trailer is connected. That being said, the work around is equally odd. As most of these will utilize a 4 Flat harness for the power and signals, you simply need to install another 4 Flat harness, like the Hopkins Endurance # HM48030, directly to the corresponding wires behind the tail lights. This is a pretty common occurrence with the Ford F-Series trucks.
    view full answer...
  • Error on Ford Truck With Skull LED Hitch Cover
    I assume you have a Ford truck, as we see this issue on 2015 and up Fords when using LED hitch covers like the Skull with L.E.D. Eyes Trailer Hitch Receiver Cover # CR-018. These covers wreak havoc with Ford trucks so the only solution is to hardwire in a separate 4-way, the Hopkins Endurance 4-Way Flat Trailer Connector Socket # HM48030. You would still get the error if you tapped into your current harness, so you would need to hardwire the connector to a powered circuit different than...
    view full answer...
  • Options for Connecting to 6-Way Square Connector of Dutchmen RV
    The Jayco 6-way square connectors use a standard connector but a unique pin out. So what that means is that the # 30104 could work for you but you'd have to cut the wires to match the different pin out which we don't have info on. Or you could cut the 6-way off of your Dutchmen and wire a standard 4-way to it instead like with the # HM48030. The 4-Way vehicle end functions will be oriented in the 4-Way as follows: Exposed pin = ground (white wire on harness) Next pin = running lights...
    view full answer...
  • How To Add A 4-Way Trailer Wiring Harness To A 1997 Land Rover Discovery
    According to my research, the 1997 Land Rover Discovery has separate turn and brake lights so the the best option we have for you to install a 4-way is with the Upgraded Circuit Protected Tail Light Converter part # 119178KIT. This comes with the circuit tester you need to find the correct wires, the connectors you need to attach to these wires, and the converter box to combine the stop/turn signal circuits. The Hopkins Endurance 4-Way Flat Trailer Connector Socket part # HM48030 does...
    view full answer...
  • Replacing Damaged Vehicle-Side 4-Pole Connector on Curt Wiring Harness
    Yes, you can replace just the damaged connector on the 4-pole harness on your 2013 Hyundai Santa Fe GLS. Hopkins part # HM48205 includes both vehicle- and trailer-side connectors (giving you a spare for the trailer) and quick-splice connectors. Similar products you might prefer include # C58044 that gives you a 60-inch length and # HM48030 which features an ergonomic-style plug. You will connect the white, brown, yellow and green wires color for color. I suggest wrapping the splices with...
    view full answer...
  • Adapting a 7-Pin European 7-Way on 1999 Range Rover to US 4-Way Flat Trailer Connector
    You would have the same problem using adapter # 118710 as you would with just splicing in a 4-Way. The adapter doesn't convert the separate signals to combined signals used by most trailers in the US. You would need to add a converter, # RM-732, which will take the separate signals and combine them. You could then wire in a 4-Way flat such as # HM48030 on the output side of the converter.
    view full answer...

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