"4.56--thats crazy!"

Alright everyone here says ohhh 32s, go 4.56 and dont look back you will get ur gas back and the power is awesome...then I ask 4 wheelparts and they say oh no you should do 4.11 ur gas mileage will be terrible with 32s and 4.56 unless your going to run around 35s. Broncos, Trucks, blazers, I havnt heard many of them running 4.56 unless they are going alot bigger then 32. The ratio chart says 4.56=straight up power with 32s and great gas mileage with stock 3.55. (auto may i add) So whats the deal, I hear two different things all the time? Is it the size of the engine in the other trucks ect...?
"Depends on what your looking for..."-whatever, im looking for what everyone else was looking for when they say I LOVE MY 4.56 AND 32s!
(oh and im not being mean...i thought it sounded better with a little satire : )

How important is gas mileage to you? If it's pretty much strictly trail it doesn't matter your gearing, mileage sucks on the trail regardless. With bigger tires, lower gearing means more power, less speed, and more gas.

3.55 and 32 is not optimum mileage. its optimum suckage. 4whlprts dont know what there talking about. i've run 4.56s with 31s 33s and 35s. 31s were awesome, fun to drive and very much streetable even on the highway. 33s were about perfect with it. great balance of gear and tire. with 35s, it absolutely sucks balls. mileage was about the same with 31s and 33s, i've lost some with the 35s. so, do 4.56s you wont regret it. do 4.10s, and i guarantee you will.

Well its a DD and I drive 2 hours to college and like 3 1/2 to Uhwarrie, it definantly sees alot of roads, and my schools in the mountains. In other words gas mileage is a good factor but from everyones response to 4.56 they seem to love it. Then 4 wheel parts says it will suck... Im tryin to stick to the advice of all you people but then a 4 wheel shop says the opposite and its like huh??

there is no perfect ratio. It depends on engine size (the smaller the engine, the more gear it will need to push big tires), engine health, tire size, wheeling habits, typical terrain that the Jeep will see, vehicle weight, ratio of highway-miles-to-trail-miles, auto or manual, and especially personal preference and experience... and I'm sure there's more.
Don't forget that engine RPM on the freeway is not a direct comparison to MPG because the engine doesn't use the same amount of gas per rotation to maintain a particular speed with 4.56 and 3.55 gears.
I have a heavily armored and very "prepared" MJ, 4.10s, 33s, manual trans and a tired 4.0L and I dream of the day I can get 4.88s or maybe even 5.38s.
Jeep on!
--Pete

J98cherokee said:

Well its a DD and I drive 2 hours to college and like 3 1/2 to Uhwarrie, it definantly sees alot of roads, and my schools in the mountains. In other words gas mileage is a good factor but from everyones response to 4.56 they seem to love it. Then 4 wheel parts says it will suck... Im tryin to stick to the advice of all you people but then a 4 wheel shop says the opposite and its like huh??

Click to expand...

Could we sticky this chart?

http://www.4lo.com/calc/geartable.htm

I take it that the ratio charts dont really match up to Cherokees as well?

any thread you look at on here will tell you 4.56s. my experience tells me 4.56s. when i was doing gears, shops told me 4.10, i knew better. dont make a mistake.

gcurtis said:

Could we sticky this chart?

http://www.4lo.com/calc/geartable.htm

Click to expand...

no, because those charts arent accurate.

Ramsey said:

no, because those charts arent accurate.

Click to expand...

Why don't we make up one that is?

the gears and rpm completely change based on what engine,tranny,t-case combo your running.

in most jeeps, 33's with 4.56 seems to be the norm for overall performance.

but for example my buddy who only does chevy truck performance, says his truck with 4.56 screams over 3300RPM. it all depends on the driveline.

do a search on the gearing in turbo 350, turbo 400, 700R4 and others, and compare that to the jeep AW4, AX15 or others. you'll see that the ratios in the tranny's are completely different.

i personally would take the experience of people who actually drive these things on a daily basis, over the sales people anyday. when you pick up the phone to order your parts, there is a 50/50 chance that the guy selling you the parts has never been behind the wheel of a 4x4 and has no clue what he is talking about.

and if you are concerned about the people here giving you partially incorrect info, then make sure you ask specific questions. when you ask if 4.56 and 33's are a good match for example, make sure you say if it's a trailer queen, a daily driver, or a dragster. now i did read that you said it was your DD, and from all of my research, and from reading 5 different jeep forums, i also agree that 4.56 and 33 should do good.

i went from 3.55 to 4.56 with an AW4 auto and np231, with 32's then 33's then 35's, with the 32 and 33" tires, the 4.56's felt the same, with 35's i with i could have went the 4.88's but i have an 8.25.

so yes, do the 4.56's

i went 4.10's with 32's. I do most street and offroading prolly once a month. They work great for me offroad and im getting 19 street 21 highway mpg

gcurtis said:

Why don't we make up one that is?

Click to expand...

You don't need a chart, you need this thread:

http://www.naxja.org/forum/showthread.php?t=46901

Everyone needs to post what transmission they are using also. Manual vs. Auto makes a huge difference. I had 32's 4.56's and an AW4 on my '94 and It was awesome. The power was in the right place in the transmissions shift pattern. 33's would be so close you'd never notice. My '97 with the same setup and 35's is off the top shift at 65 mph. It hunts alittle and is always shifting up....down....etc. The engine is most efficient at higher RPM's. I've seen a chart that shows the best power to fuel mileage RPM for the 4.0 but I can't find it. Ithink it's 2800 - 3000 RPM.

This is free info so judge it accordingly.

Well thanks for clearing that up...Im tryin to support all you er's, XJERS, NAXJERS, ??whatever... I knew you guys were right all these other biaches can take a hike, well, after they order my parts. ahHAH!

well unless i missed it, you didn't say what engine, tranny, or jeep you are talkin about. why don't you try and find a couple of examples of rigs, one with 4.11 and one with 4.56 and see how they feel. either gear will work"ok" in a jeep with a 4.0. it's just that almost everybody will someday go to a bigger tire so 4.56 would be best, and 4.56 is just that much lower gearing for the trail, which is usually preferable. i think gas mileage varies so much, that it will be hard to judge what you will get. not everybody drives the same speed, distance or RPM . i will agree that given the choice, i would go with 4.56.

i think that 4.10 would be great if you had more motor. i know the 4.0 is a great power plant but its powerband is where gear limitations come in to play. for example i ended up going to 4.10 on my full size chevy with 35" tires and it made alot of difference. in my jeep i already have 4.10 axle to put in it till i get the full widths done and i think ill end up with 4.56s and 35-37 ish tires

All the drivetrain is stock on my jeep except for the driveshaft but besides that AW4, 231, 8.25 the basics...im thinkin 4.56 is the way to go but since Id like a locker eventually i might as well save up for both so I dont have to do two seperate installs.

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