I'm running 37" MTR's with RK 3.5" springs (netted 4" lift) with factory flares. I had an AEV bumper (2008 model) but got rid of it because it rubbed too much when wheeling - even with the front sway bar connected. My wheels are 4.75" back spacing. Bumpstops are ~4.5" in front and ~3.5" rear.

On road, you will be fine. The only rubbing I had was minor on the front LCA and edge of AEV bumper at full turn (factory steering stops). Once I got off road and disconnected the front sway bar, my fenders were the least of my rubbing issues. When tucked, the front tire would rub the top of the spring perch as well as LCA's. I had to add 1.25" spacers to solves those issues. If I never made any turns, I wouldn't have these issues. Once I turn and tuck the front wheels, that's where most of my issues appear. Another issue I dealt with was stowing the links for the front sway bar when disconnected. My disconnects are Teraflex and the come with a pair of posts to mount the links in the wheel well when disconnected. I had to remove those posts and zip tie my links higher so I could clear the front wheels when turned/tucked.

I still have some minor rubbing issues when both axles are fully articulated. Sure I could add more bumpstop, but I would lose the little bit of usable uptravel I have and probably bottom out way more.

 

37x13.5 STT Pro Tires
LRG 106 Wheels, 5" backspace.
1.5" G2 Spacers take it to 3.5" backspace.
Rock Krawler 3.5" Triple rate springs, the RK02001 and RK02002.
1.25" Teraflex Body Lift
3" front bump stop extensions.
3" Rear axle bump extension and 2" rubber bump extension.
28" Fox IFP shocks
Factory flares and tubs, no cutting of body or plastic parts.
Trimmed 1.5" from back of Rubi Rails.
Factory control arms with ProRock 44 Unlimited nets 5° caster and 5° pinion.
The 37" tires folded the stock drag link in my driveway while putting a tire up on my wall block, it simply will not work.
I also like the look of the factory flares, so I built specifically to accommodate them and knowingly gave up a good amount of up travel. You can't have everything. I made up for it by going with more drop with the longer 28" shocks.

 

.... Thinking about the body lift to account for the fenders and keep to 3.5". Any cons to this?

Also undecided between STT/Toyo/BFG tires. Looking to handle TN mud and rock. Any opinions on difference?

 

No, there is nothing wrong with it.

I know, I am an odd person on Jeep forums. But.... I am a detailer, I am a paint snob, and I am OCD clean with vehicles. I hate rust, yet live in Pittsburgh PA, directly in the heart of the rust-belt.

So, I had a lot of emotional issues just thinking about cutting my body. I can't break the paint seal! If I have rust, I have to sell the vehicle! (It sucks being mental about vehicles. I wish I was normal.)

Anyways, my 3.5"/1.25" allowed me to not touch the painted body tub even once with a saw or cut-off wheel. Of course I had to shorten (cut) the rear ends of the Rubi-Rails 1.5" and re-coat that steel. My OEM flares are un-cut, so my flares still look nice (I like the OEM flare design) and my inner wheel tubs are in place.

If you ask me if I am giving up anything to do this, yes and no. I have front and rear +3" bump stop extensions. The front is the aluminum pucks that bolt to the axle side spring pad and the rear is a chunk of 3"x3" tube I had laying around that I cut and drilled and sat on the rear axle landing pad for the OEM bump stop. If I got rid of the OEM flares, I could shorten them both to about 2", and I would be able to just bottom out the 28" Fox shocks. So I am not really giving up much.

As it sets now, I can articulate and rub onto the OEM flares, but not enough to do flare damage. So I have it pretty dang perfect. All in all, I wouldn't change a thing for me on my Jeep with my wants and needs. I am totally happy, and that is all the counts.