Typically a trailer with a 7 pin plug is going to have brakes on it. You will need to have a 7 pin on the vehicle to operate those brakes. That is why you don't see ready made adapters going from less to more pins because it means you can't use the brakes which is a big problem if the trailer is of any real size. That is why you see the 4pins on small trailers because they aren't heavy enough to require brakes and can rely on the stopping power of the vehicle alone.

The correct answer is to install a 7 pin harness on the jeep and get a brake controller for it. Mopar makes a kit for the JKs.

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I agree with DiamondMox, the best way to do it is to do it right and install a full 7-pin on the Jeep and not try to make some way to circumnavigate it. Jeeps are not good tow vehicles as is and depending on the size and weight of the trailer you most certainly will want the trailer brakes fully functional.

 

What size and how heavy is the trailer you are wanting to pull?

 

yea I guess I could have been more clear with that. It’s just a basic, maybe 16’ish trailer with no brakes that I use to haul fire wood and the occasional lawnmower. The connector would really only be for the break lights

 

And most importantly does it have electric brakes. Not all trailers with a 7 pin connector have electric brakes. I had a 7 pin on a utility trailer for years so no one would ask to borrow it. When I sold my PU tow vehicle I converted it to 4 pin.

But if you install a 7 pin socket, you can either keep the 4 pin as well or use a short converter.

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I still have several laying around.

 

I had a 7 pin on a utility trailer for years so no one would ask to borrow it. When I sold my PU tow vehicle I converted it to 4 pin.

I like this idea

 

The Reese adapter mentioned above works great. Been using one occasionally for years never an issue.

If you have a 7 pin already just look behind it - sometimes there is a prewired 4 pin wire tied to the loom.

 

They do make a 4 pin to 7 pin adapter. It allows you to run the light on your trailer and the electric brake wires are there if you want to run the appropriate wiring for the brakes from the tow vehicle to the plug. I have one and it was bought that way not a hack job.

 

I put 7 pin on all vehicles and trailers. So short answer is YES you can run an adapter. You do not need trailer brakes in all applications. If you do have a trailer that requires brakes you can install a remote wireless unit on the trailer so the tow vehicle does not need to be wired.

 

Amazon has a number of 4 flat to 7 pin socket converters (using a short length of wire). Just search for 4 pin to 7 pin trailer adapter. They run from $14 up.