ok thanks That answers a lot of my questions because when i got my JK i so excited that i totally overlooked the fact that it didn't come with the tow package and was going to install one but didn't know which wiring harness to go with... again thanks

 

you can buy a converter from one to the other, but the seven pin includes things the 4 pin does not... http://www.wkjeeps.com/trailer/trailer_pinout_wk_01.jpg

I added the Mopar trailer hitch and Mopar electric wiring harness... I put pavers behind the front wheels in case I might have trouble since it was my first go at pulling my boat (18ft center console) out of the water and up an algae covered ramp (2008 unlimited).

Pulled out the boat (with a mostly full tank and a bilge filled with water - long story) out with no trouble at all... and that includes going over the pavers which I forgot to take up since I was so surprised at how easily I was pulling out the boat.

The posts on this forum had me all worried. South Florida can have some pretty slick ramps on the fresh water lakes.

 

I have a factory trailer hitch and factory wire harness I'd be glad to sell cheap.