What are the differences in the JKU JKU JKUR suspension components, specifically springs, control arms, sway bar links and drag rod length?
Internet research indicates these ride at different heights, by up to two inches, and also that you must compensate for driveline andgle and at least front axle roll with any significant lift. Did Jeep vary the control arm lengths with spring height, or do they allow differing driveline angles? Please let us know how you came to your knowledge.
I'll soon be advising, in detail, the difference between a 2008 JK (X) and 2016 JKUR.

 

Way overthinking factory suspension IMO. Different spring rates and shocks. Maybe the 2" differences you reference are throwing 4dr rubi shocks and springs on a light 2dr. There is definitely not 2" of lift difference between 4dr rubi springs/shocks compared to sport. Control arms, drag link, drive shafts....all that other factory stuff was the same turd units across the lineup. Obviously 2dr parts and 4dr parts, but no difference between sport, sahara, and rubicon.

 

I agree, makes much more financial sense for the parts to be the same. But there's all sorts of posts with stock rubicons being 1-2 inches taller than others, and also all sorts of posts that you must correct angles and rotation to avoid handling woes or driveline damage. At least one of the three above must be incorrect. I'd like to find where the fault is.

 

I think even the shocks are the same between sport/ Sahara though they weren't advertised that way many years ago. Obviously the Rubicon has a little different shock.

But agreed- control arms, drag links, all of that stuff is exactly the same. I've had my hands on all of it with doing more lift kits than I can recall. The driveshafts are something I'd like to explore if they're the same between 3.8 and 3.6 but I'm running a 2015 front ds on my 2010 and nothing has blown up so I'm guessing they're not that different. Same applies for a rear driveshaft- auto or manual, I've installed both but I don't recall a length difference....though maybe there is?

 

it all depends on how they are equipped from the factory. if you have a loaded 4 door sport and a loaded 4 door regular rubicon (not recon edition or 10A edition) they most likely have the same coils ie fronts either -18 or -19 and rears -58-59. I have put lifts on many jk's and I find stock coils on sports having the same part numbers as the rubicons when equipped the same.

 

Since the hard parts dont change, only the spring rates, has anyone modeled the system to get a calculator for control arm lengths, shock travel, etc? (Besides jeep, they probably wont share!)

 

Interesting discussion. I looked at several places including Quadtrac (2008 year) and typically the Rubicon and Sahara are about the same height but both are about 2" higher than the X.
https://www.quadratec.com/c/referenc...ngler-jk-specs

 

x2 on over-thinking it.

Take a quick look at the alignment specs. One thing that jumps out is a 'range' of numbers. For Caster (which is affected by control arm length and/or lift height and/or significant added weight), the spec is 4.2* +/- .5*. So anywhere within the range of 3.7 to 4.7 and the Caster meets the factory requirement. Why worry about manufacturing different length arms and keeping up with all the variations for this model using this specific coil vs that model using that coil when they can just throw the exact same arms on every model and have them all fall within that specific 'range'.

What it sounds like you are really asking is about aftermarket components, not stock. The time to start considering angles is when you lift it, not when you drive it off the dealers lot...

 

Rubicon and Sahara have 32" tires, the very lowest, most basic X (Sport in 10+) had 29" tires- there's your 2" difference when you figure in a smidge of height difference based on coil plus the tire diameter difference.

 

That makes sense. Always a reason!