I've seen a lot of threads come up lately asking questions about IRO's 3.5" F>R kit, so I thought we could start one
comprehensive thread to point people to the next time the question comes up. Any ZJ owners currently running this lift, please post pro's/con's, suggestions, solutions, etc.
I'll start with some basic info from IRO's site:
ZJ 3.5" Lift Kit
-3.5" front coil springs
-(4) Hydro shocks (upgrade to DT8000's $70, Bilstein $250, no shocks -$100)
-Adjustable front track bar
-Extended front and rear sway bar endlinks (upgrade to disconnects $80)
For those wondering where the rear springs are, your stock front springs are moved to the rear to (hopefully) achieve the appropriate amount of lift. The exact amount of lift to the rear will depend on how old your springs are, and if they are I6, V8, or UpCountry V8 springs.
If you're wondering where the rear track bar is, well, there isn't. To keep this kit as inexpensive as possible, IRO only included what was absoultely neccessary. Some people might feel that you don't need to do anything about the rear track bar. Some might want a relocation bracket(~$45). Some might feel the need to add a new fixed ($120) or adjustable ($140) rear track bar. Personally I think if you are going to get a new TB, spend the 20 bucks more for the adjustable.
With the kit installed, 31" tires fit without any trimming, but may rub on suspension components (such as the front LCA's) at full lock with stock rims. 32's should fit with a little bit of trimming. Of course if you're trigger-happy with a sawzall you could go 33+.
Let's just say you went with 31's - your Jeep may look something like this:
My old front springs didn't quite give me the lift I needed in the rear, so I added some 3/4" BB spacers. To center the rear axle I got a rear track bar drop bracket made by Rough Country. A set of 1.25" wheel spacers from EZ Accesory keep the 31" STT's from rubbing on any part of the suspension. However, a little flexing with the wheels turned knocked a corner of the bumper cover off a few times, but as you can see from the pic I usually just take it off anyway.
-By far the cheapest way to lift your ZJ 3.5", no extraneous stuff to drive up the price (cough Rough Country cough Rubicon Express cough)
-No rear track bar included (but then, this keeps costs down and lets you choose what you want to do about the rear axle)