35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground

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• 72 inch Trailer Axle with 2k Capacity and Hub/Drums to Match
  We have 72 inch axles that are 2k rated with idler hubs as a single part number but none that have the hub/drums on them so you'd need to order an axle with spindles only in that configuration and then add the hub/drums and assemblies like with the # T20BTR-7258 and then hub/drums # 8-257-5UC3 and then for assemblies # 23-47 and # 23-48. Then for a wheel and tire that's 15 inch with the bolt pattern you are needing the part # AM32418DX would be a great option.
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• Is Wishbone 4-Way Required for Trailer With 4-Way but 5 Wires
  Yes you should! You are on the money with what you need, a wishbone-style 4-way wiring harness for your trailer. With this style, the white is ground, yellow is left turn/brake, green is right turn/brake, and the two brown wires are the running light wires. I'm not sure the length you need though, or if 35 feet might be too long, which is the length of the 4-Way Trailer Wiring Harness - Wishbone Style # A35W42B. We do have different lengths available, which I'll list for you just in...
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• Can I Use the Quick Splice Connectors to Install a New Wishbone 4-Flat Trailer Harness
  Yes. There's no reason you can't use something like the Quick Splices - Self-Stripping Connector - Closed Port - 14-16-18 Gauge - Blue - Qty 1 # SWC502905-1 to install the # W002230 on your trailer. The # W002230 uses 18 gauge wiring, so the # SWC502905-1 would be the recommended quick splices assuming that your trailer also uses 14, 16 or 18 gauge wiring. I've also linked all of our quick splice connectors to this answer in case you find that you need something sized differently.
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• Gauge of Wiring in 35 Ft 4-Way Trailer Wiring Harness # A35W42B
  The gauge of the wiring in the 4-way kit part # A35W42B is 18 gauge.
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• Can Electric Trailer Brakes Ground Through Aluminum Trailer Frame
  Typically for aluminum frame trailers we recommend running the ground wire of each assembly all the way back to the main ground harness of the trailer up by the coupler as aluminum does not conduct electricity well and doesn't always work well for brake grounds.
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• Is Optronics Trailer Wiring Harness # A35W42B Copper Core or Copper Clad Aluminum
  The wiring of the 35 Ft 4-Way Trailer Wiring Harness # A35W42B is copper and not copper clad aluminum.
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• Heavy Gauge Wiring For Lighting Functions on Trailer
  The 4 pole wiring harnesses we offer for trailers are pretty consistent when it comes to the wire gauge. The right turn/brake, left turn/brake and running lamp circuit wires are typically 18 gauge and the ground wire is typically 16 gauge. This is pretty much industry standard. However, the Hopkins Easy-Pull harness, part # HM38136 has a design that will eliminate the typical failure point of a 4 pole trailer harness, which is the point where the harness meets the plug. The plug features...
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• How Many Wires are Typically Ran to Trailer that Only Uses Lighting Functions
  Typically you only need to run three/four wires for standard trailer lighting. One for running lights to each assembly and then two for each stop/turn light. Sometimes you have to run the ground wire to each assembly but typically they ground through the hardware and that's not needed. I attached a diagram that shows how trailers usually wire up. The style of connector usually installed on a trailer like yours is a 4-way flat like the part # A35W42B which comes with 42 inches of...
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• Wiring 3-Wire Lights to Boat Trailer with Wishbone 4-Way Harness
  It sounds like you are using a wishbone harness to re-wire your trailer. A wishbone connector has a brown/green wire for the running lights on the right side and a yellow/brown wire for the left side running lights. You will also have a yellow wire that is for the turn signal and brake lights on the left side, and a green wire that is for the right side turn signal and brake lights. The white wire, as you mentioned, is for ground. On your trailer lights, most likely the red wire is...
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• Trailer Wiring has 3 Wires for Brakes But Magnets Only have 2 Wires
  Electric trailer brake magnets only have a power wire and a ground wire (doesn't matter which is which). The power wires will attach to whichever of the 3 wires carries the brake signal from the brake controller. One of the other wires must be a ground but you can ground the magnets to any clean metal surface. The third wire could be for something else or it could be a power or ground that tees off from the main ground/power wire.
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• How To Rewire Small 4-Way and Large 7-Way Trailers
  It sounds like you are either trying to wire a new trailer or rewire an old trailer. If that is the case then I do have options for you but I do not have any reference to an "elicit axle/trailer". In order to wire/rewire your trailer we will first need to determine how many powered circuits it has. The majority of smaller trailers will only have three powered circuits which are for left side stop/turn lights, right side stop/turn lights, and running lights. If this is all you have then...
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• How to Change Wiring of 1977 Amerigo Camper Trailer to Match 7-Way Format on Tow Vehicle
  No worries. If your trailer does not have brakes its wiring may well be the simple 4-pole format using connectors like the one in the linked photo. The photo shows the usual wire colors and functions associated with each pin BUT wire colors alone are not a reliable way to know how to wire up the trailer, especially an older one. Testing is the way to go and it is easy enough to do. You can confirm what wire does what on your trailer by using a charged 12V battery (like the one in your...
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• Installing 4-Way Connector on Trailer with 5 Wires
  If you have 5 wires on your trailer and a 4-pin connector, you most likely had what is called a wishbone harness on the trailer like # A35W42B. On a wishbone harness, you will have two wires attached to the running light circuit because there is one wire for each side of the trailer. I recommend testing the wires on your trailer with a 12V battery so you can verify each of their functions. Going by color alone is not the best method, as manufacturers and aftermarket wiring can change...
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• Heavy Gauge Trailer 4-Way Wiring, 16 Gauge
  The longest 4-way harness we offer that has all 16 gauge wire is the Wesbar Harness part # W787274 which is 14 feet long. For one that is 30 feet long that has a 16 gauge ground wire and 18 gauge signal wires you would want the part # W002230.
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• Troubleshooting Trailer Brakes Where Only One Assembly Locks Up
  The brake assemblies all will receive the same amount of power from your brake controller so the issue is the brake assembly that is locking up. Most likely it's adjusted tighter than the others which is causing it to lock up sooner. That would be the first thing I'd check. The trailer wheels should be able to turn by hand if they are off the ground but you should be able to hear the brakes drag on the drum slightly. Check to see if the one that locks up is harder to turn and that would...
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• How To Wire a 5th Wheel for Triple Towing a Trailer with Brakes
  It is possible to triple tow (1 tow vehicle + 2 trailers) when both trailer's have brakes but this would mean that the brake output wire that runs from the brake controller in the tow vehicle to both trailers would need to be at least a 6 gauge at the minimum so you don't have issues with voltage drop. Also, the number of braked axles cannot exceed what your brake controller is capable of handing which most are usually four. In order to obtain the needed length of 6 gauge or greater wire...
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• What is the Wire Gauge on 10 Inch Electric Trailer Brake Magnets
  The magnet wires on Electric Trailer Brake Assembly # A35W42B are 18 gauge. The wiring going to the brakes from a trailer connector is usually larger such as 10 gauge # 10-2-1.
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• What is Wire Gauge of Optronics 4-Way part # A35W42B
  All of the wires in the Optronics 4-way wiring harness part # A35W42B are 20 gauge.
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• How To Wire A 7-Way Trailer Connector With A Wishbone Trailer Wiring Harness
  The best way to wire a 7-way plug on your trailer that has a 4-way wishbone harness is to use a junction box like part # 38656 from Spectro. The wishbone harness has two separate running light brown that connect both sides of the trailer running lights without the need to run a jumper wire between the two sides of the trailer. The # 38656 junction box will give you a nice way to wire together the trailer's leads and the 7-way plug like Hopkins part # H20044. You would use the junction...
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• Do the Ground and Power Wires From First Brake Need to Go to the Same Wires on Second Brake
  Great question! For the second brake it does not matter which one is connected to your 12V power and which is connected to ground. Just like on the first brake that gets spliced into the main 7-way wiring, the wires on the second brake are interchangeable. One should be connected to power and the other to ground.
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• Wiring Electric Trailer Brakes with Magnets that Have 2 White Wires
  It sounds like the magnets or their wiring could be bad. Your 2012 Chevy Silverado 2500HD is probably sensing the wrong resistance from the trailer brake magnets and that is why you see that warning message. When magnets have 2 of the same color wire it usually means that you can use either one for either function. The black wire with the 12 volt power should not be attached to the brakes. Only the blue wire should connect to the brakes. The other magnet wire should be attached to...
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• Replacement Trailer Side 4-Way Flat Wishbone Trailer Connector
  It sounds like you need a replacement 4-Way wishbone trailer side connector like # A35W42B. It is a 4-Way harness but has 5 wires, 2 of which are for running lights. I have included a link to a video showing a typical wiring and light replacement for you. If you need to plug a 4-Way flat trailer side connector into a 5-Way flat on a vehicle, normally you will not need an adapter because a 4-Way can plug into a 5-Way most of the time. If you are actually looking for something else let...
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• Replacement 4 Way Wiring Harness for Yacht Club Snowmobile Trailer
  You're on the right track! If you're wanting to install a new 4 way connector on your snowmobile trailer you can use the 35-ft 4 way Trailer Wiring Harness # A35W42B. This is a wishbone style harness that comes with the tail light wiring already split up to allow you to more easily run the wires down the sides of the trailer to the lights. This wiring harness has 35-ft of wiring to accommodate even the longest trailers and can be trimmed down as needed to accommodate for shorter trailers....
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• Replacement Trailer Side Wiring Harness for a 1996 Yacht Club PWC Trailer
  Trailer side wiring harnesses are not specific to the trailer so you can use any one that has the proper connector and length for your 1996 Yacht Club PWC trailer. I have included a link to the trailer side harnesses for you. If your trailer has a 4-Way flat connector a popular option is wishbone harness # A35W42B. A wishbone harness has 2 wires connected to the running light pin so you won't have to run jumper wires from one side of the trailer to the other for running lights. If...
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• 7-Way Trailer Wiring Setup Recommendation for a Tandem Axle Trailer
  A 4-way trailer wiring harness wouldn't carry a brake signal so it wouldn't matter how many axles you would have on a trailer that has a 4-way. A better option would be a 7-way as that style of harness does carry the brake signal. Starting with a trailer side 7-Way connector you can use # H20042 which is 3 feet long. It doesn't have to be long though because it is going to the junction box. Speaking of junction boxes you can use # 38656. I have included a picture showing how it...
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• Installing a New Trailer Connector that has 2 Brown Wires on a Trailer
  It sounds to me like you have a wishbone wiring harness on your trailer similar to part # A35W42B. Your trailer may not have a 4-way but the concept is the same. The brown wire is traditionally the running light circuit and a wishbone harness has two of them so that one can be run down one side of the trailer and the other down the other side. It keeps you from having to jump the running light circuit across the trailer somewhere. If I'm misunderstanding something and this doesn't...
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• How to Wire a Trailer so that Second Trailer Could Be Towed Behind It
  The correct part you would need would be the 4-Pole Wiring Harness part # 118603. You would need to use quick splices like part # SWC501746-1 to connect the wires of this harness to the correct wires of your travel trailer taillight wiring. The brown wires will run to the running light circuit, the green to the right stop/turn, the yellow to left stop/turn and the white to the ground circuit of the trailer. This will give you all of the taillight signals on a 4-way that you would...
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• Wiring Brakes On Tandem Axle Trailer
  Typically trailer wiring is color coded. The brake circuit is usually a blue wire which travels to each brake magnet, where it is attached to one wire from each brake magnet. The other wire from each brake magnet will ground to the trailer frame. I have attached a drawing that shows how the wiring is typically run for brakes on a trailer. I have also attached a link to trailer wiring diagrams that may help.
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• Trailer Wiring Connector for Triton 8x10 Aluminum Snowmobile Trailer
  For your wiring, you will need to test your wire functions to know which one connects where. I recommend using a 12v battery and simply connecting the negative terminal to the trailer frame and then connecting the power to each wire at the connector individually to determine function. It is not uncommon to have two wires running to one function location for each side of the trailer so there aren't any jumper wires across the frame needed from side to side. I've attached an article...
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