Adapter to Use 7-way Wiring from a Trailer with a Truck That Only has a 4-way

Question:

I am considering a truck with a 4 pin plug. I have a trailer with 7, but it is only 1700 pounds and the wire for hydraulic brakes is not used since brakes no longer function and trailer is so light. I dont need to run a charge to the battery and battery runs nothing while in transit. I turn it off. I only need Left, right, brakes and running lights. wouldnt a 4 pin work or am I missing something?

asked by: Donald F

Helpful Expert Reply:

You are correct, if you are not using the 12v line for the battery and the line for the brakes then you do not need a 7-way. The easiest thing for you to do in order to use your trailer with a truck that has a 4-way connector would be to use the Adapter 4-Pole to 7-Pole and 4-Pole # 37185. this will adapt the 4-way on your truck into a 7-way and a 4-way. The adapter has additional wires for the brake and charge line but you would just not hook those up since they are not needed, you can just tie them up out of the way in case you wanted to add them later. There is also a white wire that will be attached to the vehicle frame for a ground (this needs to be done regardless of if you use the other wires) and a purple wire if you want to wire your reverse lights.

expert reply by: Scott S