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CURT




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Always the correct part
We know our products
Quality Products
Free Shipping!
Some manual wiring required
Warranty: One-Year Limited Warranty
Installation Time Exact (Minutes): 0
There are several different types of connectors used to supply power from a tow vehicle's electrical system to a trailer's wiring system. Some trailers only need the bare essentials -- running lights, brake lights and turn signals -- while others require a connection for reverse lights, electric brakes and auxiliary power. With connectors ranging from simple to complex, it may be the case that the connection between your vehicle and your trailer is not a perfect match. For example, your truck may be equipped with a 6-way round socket, but your trailer may have a 4-way flat plug. For this very common problem, CURT offers a quick and simple solution in the form of an electrical adapter. An adapter is an electrical device that allows a connection to be made between a mismatched trailer plug and vehicle socket. It easily plugs in your vehicle's electrical socket and usually requires no additional wiring. CURT offers an array of adapters to accommodate most types of plugs and sockets, including 4-way flat, 4-way round, 5-way flat, 6-way round, 7-way RV blades and more. This special dual-output electrical adapter is actually designed to adapt a 4-way flat vehicle socket to fit multiple trailer plugs, including a 4-way flat and a 7-way RV blade connector. Some manual wiring is required. This multipurpose socket also comes with dust covers, a mounting bracket and all necessary mounting hardware for a complete installation. All CURT wiring and electrical products come with a one-year limited warranty to give you the assurance you need to tow with confidence.

CURT offers a variety of high-quality trailer hitches and accessories for select vehicle models. Find the perfect fit for your towing needs at TowUniverse.
CURT, a Lippert brand, offers a complete line of towing products and is the leading manufacturer of custom-fit trailer hitches. We offer the broadest selection of custom-fit hitches, and each one is designed, welded, and coated in Wisconsin.
CURT is also a leader in flat towing products, as well as 5th wheel, gooseneck, and weight distribution hitches, ball mounts, electrical components, cargo solutions, and other towing accessories.
For everything from passenger cars and vans to full-size pickups and SUVs, CURT is 'The First Name in Towing Products®.'
Experts available to answer your questions
Call 888-634-9494Rediscover "Us" Time | Tested. Proven. Safe. Towing Products
The 4-way flat electrical adapter converts a vehicle's 4-way flat trailer connector to other trailer connector types (6-way round, 7-way RV blade, or dual 4-way flat). This allows you to tow trailers with different connector styles. Single-output models (57184, 57183, 57185, 57626, 57676) convert to one connector type; dual-output models (57604, 57624, 57672, 57674, 57102) provide two different connector outputs simultaneously.
Yes. Your vehicle must be equipped with a 4-way flat trailer connector. If your vehicle does not have one, you will need to install a custom wiring harness or other 4-way flat trailer connector before installing this adapter.
Both convert a 4-way flat connector to a 7-way RV blade. The difference is that 57185 includes a mounting bracket, while 57184 does not.
Both convert a 4-way flat connector to a 6-way round. The difference is that 57626 includes a mounting bracket, while 57183 does not.
Curt offers three dual-output models that provide both a 4-way flat and a 7-way RV blade output: part numbers 57672, 57674, and 57102. All three include a mounting bracket.
Curt offers two dual-output models that provide both a 4-way flat and a 6-way round output: part numbers 57604 and 57624. Both include a mounting bracket.
You will need: a 1/8" drill bit, drill, Phillips screwdriver, wire stripper, cutting tool, terminal crimpers, and a test light. The manual also lists three self-tapping screws (#10 - 1/2") as required, though these are not included with the product.
No. The three self-tapping screws (#10 - 1/2") used to attach the mounting bracket are not included and must be purchased separately.
Mount the combination harness in a location on the tow vehicle that is within reach of the trailer's wiring harness and near the center of the vehicle. The mounting bracket (if included) should be attached to the vehicle's bumper or other suitable surface.
Yes. You must drill two 1/8" holes: one for the grounding point and one (or more) for the mounting bracket. Before drilling, you must check for brake lines, fuel lines, wiring and other components that may be hidden behind or under the surface to avoid damage.
No. You must never attach the mounting bracket directly to the hitch by cutting, welding or drilling into the hitch. Mount it to the vehicle's bumper or other suitable surface instead.
The adapter uses four wires: Yellow (auxiliary or back-up lights), Blue (electric brakes), Black (positive power with appropriate inline fuse), and White (ground). All wires except black and white must be connected using 12 gauge (minimum) wire and butt connectors to the appropriate vehicle functions.
The white wire is the ground connection. It must be attached with a ring terminal to a 1/8" hole drilled in a suitable grounding point on the vehicle using a #10 - 1/2" self-tapping screw. This ground connection is required for the harness to work properly. The white wire on the vehicle's 4-way flat connector does not support the ground (-) functions of the combination harness.
Yes. The black wire (positive power) must be connected with an appropriate inline fuse. The manual does not specify the fuse amperage rating.
Use 12 gauge (minimum) wire for all connections. The manual specifies this minimum gauge for the remaining wires (yellow, blue, and black) when connecting to appropriate vehicle functions.
Failing to properly ground the product can cause loss of warranty, overheating and potential fire. The white wire must be securely attached to a clean grounding point using a #10 - 1/2" self-tapping screw in a 1/8" hole. The area must be clean of dirt, debris or undercoating.
Before drilling, you must check for brake lines, fuel lines, wiring and any other components that may be hidden behind or under the surface. Drilling into these components can cause damage and personal injury.
Do not exceed the product rating or the tow vehicle lamp load rating, whichever is lower. Exceeding either rating can cause damage or unsafe operation.
Confirm proper function with a test light or by using a properly functioning trailer. This verifies that all connections are working correctly before towing.
Secure any loose wires using cable ties or equivalent product to prevent them from moving, catching on components, or becoming damaged.
Your vehicle must have a 4-way flat trailer connector. If it does not, you will need to install a custom wiring harness or other 4-way flat connector first. Check the part number table to confirm the adapter converts to the connector type you need.
You must purchase three #10 - 1/2" self-tapping screws for the mounting bracket. You will also need an appropriate inline fuse for the black (positive power) wire; the manual does not specify the amperage.
Yes, you must drill two 1/8" holes: one for grounding and one for the mounting bracket. Before drilling, check for brake lines, fuel lines and wiring behind the surface. Never drill into the hitch.
Yellow = auxiliary/back-up lights; Blue = electric brakes; Black = positive power (needs inline fuse); White = ground (must be properly grounded or warranty is void and fire risk exists). Use 12 gauge minimum wire and butt connectors.
Proper grounding of the white wire is critical. Failing to ground it properly can cause loss of warranty, overheating and fire. The grounding point must be clean of dirt, debris and undercoating.
Test with a test light or by using a properly functioning trailer to confirm all connections work. Secure loose wires with cable ties.
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