Congrats to Inked33 and to Gasman.
I'll second the AEV recomendation. AEV = American Expedition Vehicles. I.e., not American Rock Crawling Vehicles. While their lifts and other products work perfectly well for rock crawling, their focus is on Jeep JK's that drive and handle great on road as well as off road.
I have an AEV lift and ride, handling, sure footedness, steering feel, road manners, body lean - all better than stock. [For frame of reference, my wife also has a four door JK Rubicon that began stock, as all do, and now has the TeraFlex 2.5" budget lift - the spacers - with shock extensions and still rides on the stock wheels and tires with SpiderTrax 1.5" hub centric wheel spacers .]
I'll admit that I have enough red neck in me that, at my 10yr old son's urging, I went with the 4.5" lift and 37's. On the other hand, the Jeep is fantastic on the road with the AEV lift and 37's. Those who have the 3.5" lift, which accomodates 35's, pretty uniformally report that they are as pleased as I am. I have only read of one AEV customer that was less than very pleased. (And that one customer eventually reported that he too was pleased, which I believe indicates that intial issues were not AEV issues but installer issues.)
One benefit of the AEV lift is the engineering that went into it. One of the JK's leading suspension development engineers now works for AEV, and it shows. The lift addresses all suspension, steering and handling issues that need to be addressed with any lift for top flight results as well as a few issues that Jeep didn't address as well as they could have in oem configuration - like caster, front control arm angles and length, panhard/trackbar relocation with regard to both axle displacement the result of taller springs and height to improve roll center geometry to reduce body lean, drag link relocation to improve Ackerman angles and steering feel and performance. An impressive attribute of the AEV lifts in my opinion, a negative is some others' oppinions, is that AEV addresses the panhard/trackbar issue and the front upper/lower control arm issues without resorting to adjustable bars or arms; they are relocated to their respective correct new positions for the AEV lift, with different locations for the 3.5" vs. the 4.5" lifts. (The vigor with which some argue that fixed but correct length/location arms and bars is a drawback never ceases to amaze me; I find it an attribute since AEV has done the engineering and experimentation for the customer rather than leaving the customer to fend for themselves regarding the ONE correct setting for each of the arms or bars. It has occurred to me that one reason for the all but uniformily excellent customer reports on AEV lifts results from the lack of user screw-up-able adjustable anything on the AEV lifts, and that the constant request for help with other lifts for this lift issue or that lift issue posted on JKOwners.com, JeepForums.com or other forums and are attributable to customer adjustable major elements, like control arms {and so pinion angle} or panhard/track bars.)
AEV does on site conversions including their Expedition Packagee and Hemi conversions, but they also sell all parts or kits individually. AEV's sister company is a tier three supplier to Chrysler and other auto makers and they make most of the parts they offer in-house. Also, AEV does a lot of work on Jeep's concept and "show" vehicles. I suggest that you all take a look at AEV's web site:
http://www.aev-conversions.com
I have driven a four door JK equipped with a Rubicon Express 3.5" lift and 35's and it drove well. But I would and did go AEV! The TeraFlex 2.5" budget lift - the spacers, which provides about 3.5" in front and about 2.5" in the rear, is an inexpensive and pretty good way to improve the JK and to fit 35's with some minor trimming required on some but not all Jeep/tire combos. As I wrote, my wife's JK four door has this budget boost. The Jeep rides like the day we picked it up, handling is unnaffected though steering is slightly flightier - but not enough that my wife noticed it - because caster reduction the result of the spacers is not addressed. Axle offset due to the lift is noticable only when you look for it.
BTW, you will need either new wheels with about 4.75" of backspacing or less or 1.25" or larger wheel spacers to accomodate 35" tires on stock Rubicon wheels. If you use spacers, a quality hub centric spacer like the SpiderTrax is the only safe route, lug centric spacers are trouble waiting to happen, imo.
Personally, I think the JK four door needs about 3.5" and 35's both for looks and to overcome some length/high center issues.
Gasman, with 35" tires you may find your Rubicon 4.10 ring and pinion (axle) ratio fine, but a lot of owners don't. With 35" tires, your 1:1 fifth gear in an standard transmission is about equal to the overdrive sixth with original tires, with an auto, your 1:1 third is about the same as the too sttep O/D fourth was.
Inked33, with the Sport, you probably have ~3.21 R&P ratio, 3.73's if you selected that option or got lucky. Some owners find 3.73's and a standard transmission acceptable, fewer find the 3.73 and auto acceptable, very few the ~3.21's with larger tires and either transmission.
Re-gearing should run +/-$1,400 or so. With 35's and the 3.8L engine, I would suggest 5.13's, some prefer 4.88's and a few 4.56's. The 3.5" Rubicon Express and 35's equipped four door JK I drove had 5.13's and I thought the 5.13's were just about perfect.
My four door JK has the AEV Hemi in it and 4.88 gears. Even with the Hemi power, I think I would have preferred the 5.13's.
Here is a phot of my JK just before it left AEV (I had AEV do a turn key Jeep for me.):
BTW, I may be a big fan of AEV, but I don't work for them or have any financial interest at all, I'm just a very pleased customer.
JPK