jshultz78

I just got my 31's today, haven't even put them on the jeep yet, but thinking ahead, Probably going to add a winch bumper and a winch, possibly a rear bumper, which gear ratio would be best suited for the added weight? I'm leaning toward 4.10s just to get it back to stock, I may do some light mountain riding a few times a year, but it's 3.5 hours away from home, so I'd need to do something that's still highway/gas friendly. Not planning on going taller than a 31" tire, not a fan of hacking up a car to make tires fit.

EZEARL

4.10's would work well for you. Many here use stock 3.55's and 31's with no issues. Ever seen this chart?
https://www2.4wheelparts.com/article...-tire-diameter

jshultz78

Yeah, I've been reading and reading for the last few weeks about tires and gears. lol. I was gonna do 30s but found a killer deal on some 31s. I'll probably get them on the jeep tomorrow night. Mounted/balanced them tonight. I may be happy with stock gears for now, just wondering about the added weight. Defiantly gonna get the brakes upgraded to the dual booster. It didn't like the 235s going down a steep incline lol.

EZEARL

Just checked and the weight difference between a popular A/T tire in 235 and 31 was only 7lbs. 33's were 18lbs.
No experience with the dual booster upgrade but have read nothing but positive results.

jshultz78

I guess I could always lose the doors for some weight reduction. haha

tinytrax78

i wish i had 4.56 gears over my 4.10s but im running a 34" tire too so with 31s i think your safe with 4.10s unless you are gonna go big some day

EZEARL

That would work. Just don't lose them too good. LOL

Desertfox1023

It's a waste to re-gear to 4.10s for 31s
I'd hold out on a regear for when you go to 33's then go 4.88s as you'll end up on 35s eventually.

texastaz38

I stayed with my 3.55 gear for now. We only do light off-roading, fire roads and mild trails. No serious rock climbing or silliness. The stock gearing has been fine for all but one trail that required a little lower gearing. Easy fix, shifted to 4 low and went on about my business. Problem solved. I might also add that my xj is 2.5 liter, 4 speed. If it works for me, it should be fine for a 4.0 automatic.

Happy Jeepin'
TexasTaz38

nickfancher1

texastaz38

410.s tend to be found in the 2.5 liter with an automatic to the best of my knowledge. Ive had 3 with standard transmissions and all had 3.55 gears in them.

TexasTaz38

jshultz78

Got them on, maybe, MAYBE a very tiny loss of low end get up and go, and my trans temp gauge maybe went up 1 degree, but I can see where the brakes on these things aren't their strong point. haha. Is there ANYTHING I can do to help the brakes out short of doing the booster swap. I have no idea when I'll get another day off to go junkyarding. I may be able to get one or two clicks out of the rear adjusters, the rear wheels spun pretty free when I had it in the air. What about doing slotted rotors?

TrailerTrash

One thing you can do is check out the part of the knuckle that the brake pad edge slides on. There is probably a deep groove worn in and that prevents proper braking

Outlaw Star

Not all did. Some of the autos had 4.56 and some of the manuals had 3.55 instead of 4.10. My 4cyl, 4spd originally came with 3.55's.

bad_idea

I have 4.10s with my 33x12.5s, 4.0l, AW4. Speedo reads accurately, meaning I am back at stock ratios. Peppy enough. Not a Corvette, but does well.