I swapped my journey sways for S sedan sways (purchased from Rochester) and the OD of the tubing is the same, and the weight is very similar. I assume the tubing wall thickness is a bit more on the S sways but that's it, not much difference in road handling IMO. I have coils and low profile 20s so the ride is already pretty firm. I think the S package taken as a whole will be more significant, but just the S sways not so much.
Here's some comparison pics of the rear sways that I mic'd, the cleaner one is the S sway, and it mic'd thinner but probably just the dirt on the journey sway, they were the same OD.

 

Awesome! Thanks for the pics! I did some due diligence too..I pulled the part numbers of the rear sway/stabilizer bars and compared them which, basically, confirms all the AWD RSB are the same for the Journey/non-Sport/Sport and all the RWD Journey/non-Sport/Sport are the same. So therefore in conclusion, the non-Sport and Sport RSB are 24.2mm; as confirmed above by blnewt Also the brackets and links are the same eventho the bushings aren't.

2009 Sport
56230JK000 AWD
562301EA0C RWD Sedan

2009 Non-Sport
56230JK000 AWD
562301EA0C RWD Sedan

2009 Journey
56230JK000 AWD
562301EA0C RWD Sedan

2010 Sport
56230JK000 AWD
562301EA0C RWD Sedan

2010 Non-Sport
56230JK000 AWD
562301EA0C RWD sedan

2010 Journey
56230JK000 AWD
562301EA0C RWD sedan

Bracket
L: 54614EG000 R: 54614EG000 AWD
L: 54614EG000 R: 54614EG000 RWD

Link
L: 54668EG02B R: 54618EG02A AWD
L: 54668EG02B R: 54618EG02A RWD

 

You're killing me with unintentional guilt, Brad.

 

LOL, definitely unintentional, plus it's not like we're talking any significant cash. And changing out the sways was another thing I learned how to do with these cars so it was a good lesson
Like you mentioned, if I was bone stock and switched the sways the difference may have been more substantial as well.

 

Sorry to say, the diameter numbers don't mean a whole lot. Internal thickness determines the spring rate of the bar. That makes it a more apples/apples comparison. To further complicate things, is the spring rate linear or variable. If the latter, then it's more like strawberries to watermelons comparison

 

The weight difference between the two is very minimal so the wall thickness has to be just a bit thicker, there has been a slight difference in feel and handling but really not enough to make the swap something I'd recommend.

The substantial improvement noted from those that have done the swap from the S sways to Whiteline, Eibach & Hotchkiss shows that the S sways are big step down.

It would be interesting knowing the wall thickness differences between both Infiniti sways though

 

OK. This is just a hypothesis. I think if Infiniti were to make a "softer" bar, they would make a thinner bar (i.e. AWD's 17.7mm RSB ) instead of one with the same diameter and differing internal thicknesses. Also, I think if the RWD RSBs were different in any way, they wouldn't list them as the same part #s for both Sport and non-Sport. Plus, in my case, ANYTHING will probably be better than my AWD's 17.7mm RSB...Hopefully one of the best $40 I'll spend on my G....

 

It is. The rwd sway on my x is one of the best upgrades I made to the car!

 

My comments relate to sway bars in general. From an engineering stand point, weight doesn't correlate to spring rates either. Cheaper materials may be heavier but have weaker spring rates. While comparisons of weights and diameters can be done, IMO they are flawed comparisons. What's really needed are spring rates and whether or not they are static or progressive to make accurate comparisons.

 

^^^^ +1 for possessing at least a basic understanding of mechanics of materials.

 

Understood about sway/stabilizer bars (material dynamics) in general. But in this particular case, given the info (esp the matching part#s), the RSB on the Sport and non-Sport are probably the same bar. And make a difference on my AWD G.

 

So then what accounts for the rather significant difference between the RWD Sport and the RWD non-Sport? It is just the struts and/or springs?

10Gee37exeS, how about looking up the part #'s on struts and springs.

 

I tried to look them up but seems like for shocks and springs you have to give them a call to order. So it kinda looks like it's primarily the Springs/Struts/Shocks that put's the "S" in Sport. But I can't confirm these allegations i make....

 

I'm guessing there's slight changes in spring rates w/ the sways, springs and possibly damping stiffness, that when taken as a whole would make a more noticeable change, but as individual parts not so much. I do know that the ride is firmer in the Sport as I have driven both back to back at the dealer when I bought both my previous Gs.

I doubt the RWD sways are the same since the part #s stamped on my 2 sways are different.

 

A firmer "ride" is usually attributed to spring rates and damping (struts/shocks), not to sways/stabilizer bars. Sways/Stabilizers will "tie" the suspension together so one side "knows" what the other is doing. There are instances where a well tuned Spring and shock/strut or even coilover set you can forego the rear sway...too tight in the rear you sometimes will loose inside traction taking a hard turn b/c the thicker, less-twisty sway bar will prevent the inner wheel from contacting the ground. One less wheel on the ground means less grip....On my e36 M3 I had installed H&R Sport springs with H&R non-adjustable shocks/struts with stock sway bars...Dropped the car like a sled (had to roll the inner lip of my rear fenders to fit the 17" BBS RKs, rode hard like a go-cart, but the handling was sloppy....like each wheel didn't know what the others were doing...So I added Eibach adj sways and it was a 180 degree difference...the car felt planted and corned like it was on rails...I miss my M3