Jeepnboy

4.88s are most common for 35s with a 6spd. 4.56 would be almost identical to a stock rubicon, 4.88 are lower than stock after accounting for the bigger tires. I have not driven a 6spd with 5.13 and 35s, but on paper this would be too low of gearing IMO if you plan on cruising at 70+ on the highway.

Most of you know this, but 6spd have a much lower overdrive than the autos. This is why we typically prefer higher gears than the autos. Autos definitely want 5.13s with 35s.

If I don't do a hemi, I plan on going 4.88s. Driving with 4.10s and 35s is really not that bad in a 6spd.

awkragt

I found the 35s and 4.10s to be much better than the 28s and 4.10s it came with. With 35s 6th doesn’t really accelerate up hills but it’s a great gear for cruising down the freeway, 65-75mph. The 6 speed transmission are supposed to be overdrives anyway.

lhracing

If you want test your MPG and general 70 mph driving performance just use 5th gear only, not 6th. The final drive ratio with 4.10 gears in 5th gear is 4.10:1 (4.10X1) and the final drive with 4.88 gears in 6th is also 4.10:1 (4.88X.84). In my case I have the 4.10 gears and on flat land 6th works fine, for the hills I use 5th as necessary. The fuel mileage in 5th is about 2-3 mpg lower than 6th so down shifting as necessary is not a big deal to me as compaired to loosing the fuel milage all the time (with changed gears). If I setp up to 37's then the 4.88's are what I will be changing to.

Marmot mb

35's 2.5" lift with a 1" body lift. after the 35's and 1" lift 6th gear is just a highway crusing on flat ground no head wind gear now. sucks and is a pain in the butt, but I have watched the milleage using 5th when needed and it's less than leaving it in 6 and just taking the deceleration as it comes. As you have to speed back up after you loose it.

Cheaper to stay at speed (reasonably so anyway) and use 5th or even 4th when needed.

It's a gutless pig and nothing will ever change that (except a motor swap)

Procomp Hypertech Programmer did help highway power a bit though, and am currently testing the 91 octane use and setting to see what that may do.

asjackman

I have 35"s with Rubi gearing (4.10). I plan to stay with 4.10s until I go larger.

I use 6th all the time around 60-65mph and faster. I'm in the same boat with everyone else, once an incline comes, I have to gear down to 5th, but it's nothing to regear for. I do plan on getting a Flashpaq to see if that'll give me a bit of a bump to stay in 6th at a lower speed. While offroading, I do find plenty of power due to the TC.

I am divided between 4.88 and 5.13, due to how large of a tire I plan to go with.

warlord

for me i can still use 6th most of the time.
the only time i lose it is when im driving up the del mem bridge and theres a slight head wind. sometimes i make it up in 6th and other times i have to shift.

anytime it drops below 2000 rpm exactly is when it is powerless and starts to plummit

Phishjeep

Don't use 6th gear at all. My mileage is better with 5th gear, anyway. If I were to regear, I could use 6th, but 1st is low enough as is so why bother. So it's a five speed. If I ever get my pro rocks on (44 in the front, 60 out back), and go to 37+, I'll order them with 5.13's.

rinkishJK

i think all this is also related to where ppl live. by me there is lots of mountains and hills.. not CO mtns but its definately not flat.. south jersey is flat. i find on flats 6th is fine.. pulls good. but the minute there is an incline its tough to maintain speed without flooring it or downshifting. by no means is it unbearable. goin to work today about 70mph i'm at 2100 rpm in 6th..

rinkishJK

well heres my other thing. i just switched back to 87 tune after running tow for awhile. tow seems better with 91 gas, and the 89 now for me, after tires and lift feels better low range power and with 89 gas.. there is no logic but it def fells better.. no ping issue either.. your the one that originally got me runnin tow tune.

SJ21XDC

I have a '10 Rubicon and have been running 35's with the stock 4:10 for about a 1,000 miles. It's ok, but like everyone else has said, 6th is only good on flat roads. Any incline and it's back to 5th. I did get a chance to pull my bass boat this weekend and it did ok. I will probably give it a couple more months but can see 4:88's in the future.