TeraFlex

Long arms do not give you more flex. Generally flex is limited by your shocks length, brakelines or limiting straps. But they do have better ride/handling quality over a short arm setup.

Full-Traction Suspension

Check out our 3" premium plus kit. Its a perfect starter lift and doesnt leave out parts you will buy down the road.

wayoflife

your factory arms are considered to be "short arms" but, compared to the old 97-06 TJ, they are a lot longer and, unless you are going to be installing a 4" lift or taller, are more than adequate. "long arms" are just that, longer arms that will require you to cut off and install new control arm mounts on your jeep's frame. the purpose of longer arms is intended to help restore your suspension geometry so that it's closer to stock again and among other things, the biggest benefits will be seen and felt most when driving on pavement. longer arms DO NOT necessarily provide more flex.

aside from the obvious, the lower control arms are intended to set the position of your axle under your jeep. the upper fronts are designed to set caster and in the rear, to set your pinion.

having all new adjustable control arms is nice to have but, being that you have a 4-door, you technically only need a set of adjustable front lowers as they alone will allow you to add a bit more positive caster. the rear uppers are only needed if you were to install a new u-joint style drive shaft but, this will not be needed on a 4-door.