Nice info. I'm preparing to go with 32" tires, and I was thinking that 4.11 gears make the most sense.
You may not like it if you drive steep mountains. Highway 4 in Califirnia for example, that is steep, plus the thin high altitude air causes HP loss.
like I said, my friend rig does better than mine, but he is has 32 tires, with I assume less rolling resistance as they are AT tires, not MT tires.
I believe (correct me if I am wrong) that 30 inch tires and 4.1 is about same final ratio as stock. so 32 tires makes you about 2 parts in 30 off, about roughly 7 percent.
My rig with 33 tires frequently down shifts on small freeway grades at sea level, then she is screaming in 3rd! and that is driving at 65 mph or less!
when she down shifts like that, it is best to manually shift the tranny into third so that the torque converter locks. if converter is allowed to slip, the tranny temp skyrockets rapidly. so you got to use the driver brain to know to down shift rather than simply let the tranny shift for you.
So I say that 4.1 is marginal for 32 tires, and really not good at all for 33 tires. At least that is what me and my xj friend have determined.
My rig was purchased that way, 4.1 and 33 tires. prior owner originally did the 4.1 regear when he put 30 inch tires on, but later went to 33 tires, He did regear a second time.
moral of that is, if you regear, plan on what final tire size you will go to the first time, plan ahead.
Both me and friend wish we had a higher ratio, but me more so than him, of course he is the one that needs to slow down for me. On some super steep highways, I am in second gear, which means I am turtle slow, and reving like mad.
Suggest if possible that you meet fellow xj owners locally that have done the tire and gear swap and ask for a test drive.
If you have any desire to ever go to 33 tires, do not do a 4.1 now, go higher ratio now. with 32 tires 4.1 is borderline acceptable if there are hills at all. Also on down hills, you dont get as much engine braking unless you down shift even more, and that means even down hills you end up going slower at high rpms!
also you wont have a good off road torque with too low a ratio. Fortunately I have a super high ratio Low range transfer case that mitigates that a bit.
The final ratio needs to fit the motors powerband for best results.
When I was a kid I drove a 63 VW Microbus, 1200 cc, 40 hp. Id take it camping in the mountains, (literally first gear on the shoulder of highway 80 in the Sierra's , hazard blinkers flashing, even the semi trucks in the the slow lane passed me) and my daily driver was a 61 Bug, again 1200cc. So I am used to slow, so I tolerate the wrong gears in my jeep better than most people might, and still I think my gears need to be changed, it is only time and money, neither of which I have much of.
If in your shoes, Id do a higher ratio, I think. You are at boarder line acceptable at 4.1 and 32 tires.
research it more, my advice is just piece of the puzzle. you only want to regear once.
