Am I buying the right part? What can I pull?

[ame="http://www.amazon.com/Hopkins-Plug-In-42465-Connector-Cherokee/dp/B0002Q7ZHI/ref=sr_1_1?ie=UTF8&qid=1399997102&sr=8-1&keywords=jeep+cherokee+trailer+wiring"]Amazon.com: Hopkins Plug-In Simple 42465 T Connector Wiring Kit For Jeep Cherokee, '9701: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/512TD71P4GL.@@AMEPARAM@@512TD71P4GL[/ame]
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Thats the wiring harness Im thinking about buying.

Were going to pull a trailer from Uhaul but not sure of what size an XJ can pull. Our big items are an L shaped couch, lazyboy and a double queen bed. The trip is about 1 mile with no hills. The heavy items from the storage unit are 2 1975 Honda CL360s and lots of boxes about 15 miles slight hills.

I have a class 3 hitch installed mainly for a recovery point right now.

I think I could move everything but the L couch and bikes without a trailer but it would be a PITA.

You'll be fine moving those

That harness should work, no experience here, but it looks right :P

Many people have towed much heavier loads with their jeeps... you'll be perfectly fine buddy

Looks right and you may not need the additional length of wire with the flat four connector on each end. I didn't need it for mine.

You shouldn't have a problem hauling those loads, just make sure they are positioned on the trailer correctly as to not overload the tongue.