Colorblindspy

Ok, New to jeeping and had a quick question and I hope this is a basic answer but I dont want to make the assumption and go with the wrong kit.

1. What is the main difference (This is the basic answer part I was talking about)
2. What advantages/disadvantages to I have with each kit?

07JKDakotaEd

Short arm uses the existing control arm brackets.long arm requires that they are cut off and new ones are welded on. Short arm retains the factory geometry while long arm corrects the control arm angle to the new lift height. Short arm = cheaper and bolt on while long arm = expensive and welding and labor intensive. Long arm gives you a better ride and less bump steer. Long arm is badass and short arm is ok up to a certain height (about 3") and then long arm is a better choice for ride quality.

Arcticshaun

I agree with some of this. Long are will give you more articulation due to the arms being longer than short arms. I went with a RE 4.5 short arm kit and the ride is as good if not a little better than stock with 37's. But I went with fox resi shocks all new track bar and adjustable arms and such. I did a complete kit. Now I can add long arms and all I need are the arms and brackets but I'm not doing no crazy rock climbing so no need for me. I did redo my steering also went with the high steer setup and fox steering stabilizer. I love it. I'd say if your not going to go out everyday and do some crazy rock climbing don't waste the money on a long arm kit. That's my opinion. Here's my ride.

therza

I agree with all of this, but want to clarify the "more" articulation part. The TJ's benefited greatly from long arm kits. The articulation really went up on a TJ when you added a long arm kit. (I had the TF long arm kit on my TJ and it was great.) However, I think too many people are assuming the same thing applies with JKs, or specifically JK Unlimiteds. When researching lift kits, I asked vendors for RTI scores for their long arm and short arm (if applicable) kits. Of the ones that would actually share those numbers, the differences were well below what you might expect. Measurable, yes, but worth the expense and extra installation work? I couldn't justify it. I found, based on the vendor provided numbers, less than a 10% increase in RTi scores. So I suppose it you are in need of every last millimeter of articulation, a long arm kit makes sense. If that is not a major factor (a slight increase in articulation) then stay with a short arm kit. I am running a 4.5" AEV kit with 37s and love it.

Arcticshaun

Cool where's the pics? Ur right I t
Just assumed we were talking about jk's

dinojeep

I think its important to remember, the true benefits of a long arm kit will be noticed more ON road rather than off road. Yes, you will get better articulation off road, but for most of us, we spend more time on road. And a long arm kit will have better road manners.

wayoflife

the taller you go, the steeper the angle your factory control arms or, "short arms" will sit. when significant enough, this change in geometry will effect the ride and handling of your jeep adversely. on a old TJ which had really really short arms, this was something you saw right away however, on a JK, a vehicle which comes with significantly longer control arms right from the factory, it's something you really don't need to address until you get to about 4" of lift or taller. long arms require you to install new control arm mounts further back on your frame and by virtue of this, helps to help flatten and correct your suspention geometry to being closer to stock. this greatly improves your ride and is really noticable ON PAVEMENT.

cost is the biggest advantage to short arms as they are much more affordable and require no additional labor to install. long arms cost a lot more right off the bat and require a lot of cutting, grinding, welding and or drilling. needless to say, they are expensive but, well worth it IF you are going to lift your jeep over 4". assuming you did an apples to apples comparison with 2 JK's with the exact same lift and shock lengths only one with short arms and the other with long arms, you would see less axle swipe and more accurate articulation with long arms but, the actual amount of flex would be about the same.

not true at all. long arms will not give you any more articulation than short arms, they simply correct suspension geometry after a tall lift has been installed.

"crazy rock climbing" should have no bearing whether or not you install long arms as the most benefit you will see from them is ON PAVEMENT. if you spend most of your time ON PAVEMENT, i would HIGHLY recommend long arms as the ride and handling it will offer will be far superior to short arms. trust me, i have run both setups and with 37's multiple times and even with coil overs and can tell you this from first hand experience.

wayoflife

you're saying that you tested both with the exact same lift height and exact same shock length only one with aftermarket short arms with flexable joints and one with long arms and the later did better? i'd like to see the proof of this.

RTI scores are so completely relative and will vary GREATLY depending on lift height, shock length, tire size, wheel base, tire pressure, angle of ramp, whether you do it forward or backward and the accuracy of how it's done from one test to the other. to take someones word use it as some kind a guage to determine what does better is about as good as having someone flex out on a rock and say, "hey, it flexes great".

you're talking about articulation like it means something and then say you're running a kit that uses over priced relocation brackets in conjunction to factory arms as if it should be an example of what works well? LOL!!

Rock Krawler Suspension

We have a breaking point for the JK at 3.5" of lift. Over that height we push the long arm setup for geometry purposes.

Like WayofLife said, your real limiting factory will be shock lenghs. For example, a 4 door outfitted with our 3.5" X Factor Mid Arm System will allow you to pick up one rear tire 40" off the ground with our shocks prior to having any other shock come off the ground. One of our long arm systems would do exactly the same thing number wise. However, with a long arm system, the body roll experienced will be 10 degrees less with a long arm versus the mid arm system since our systems have no naturaly binding points.


Long Arm Systems can be tailered to do many different things, like minimize natural suspension bind so your vehicle stays more balanced in off-road situations. When you are looking to do a long arm system, you will have to really look at the geometry of them to find the one that best suits your needs.

At the end of the day, it is up to you. The JK is very different than the TJ... The TJ's almost had to have long arms because the OEM geometry was so bad once they were lifted. For the JK's, that is not the case

Rock Krawler

Colorblindspy

Thank you for the responses! I guess my next question would be, if I don't plan on going past 3" of lift (possibly 3.5 but most likely not), would i benefit getting a long arm kit for the daily driver or would I be ok with a short arm kit. I know you mentioned that this mainly benefits lifts from 4" up but I have no desire to go that big.

Again, thank you for your responses.