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Help me pick Gears

Help me pick Gears

My CJ w/ 258 needs a new rear end.

I am going to take this time up upgrade, and only want to do it once. Lift is nexst on my list But I am unsure how big. Cant decided between 33's and 35's. What will probably happen is 33's for a cuple of years then 35's But I don't want to have to re-gear when (and if) I go to 35's.

So if I knew all I would do is 33's I would go with 4.10, But if I ever go to

35's would need 4.56.

My questions:

Am I better off w/ 4.56's and 33's or 4.10's and 35's?

Any suggestions?

If use matters, it's a 5speed. I am doing to for deep mud and light rock crawling, But I tend to drive this more then my Daly driver unless I am hoping on the highway, or "need" AC. But I don't want to build this to where I can't put it on the highway if I need it to.

83 CJ 8, a work in progress
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Reply to
Evan
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Hello Evan,

I just went through the same decision. I, too, have the 258 and a 5 speed. I now have 33s but may one day go with 35s. I decided to go with the 4.56 and have no regrets.

Jim

Reply to
Jim Meyer

What rpm do you turn on the highway say at 65 mph with that setup?

I might be in need of a new rear end before too long and am curious.

I am turning about 2300 in 4th right now with 3.31's.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Jim Meyer wrote:

Reply to
Mike Romain

Having installed 4.10 for 33" tires several years ago, I knew within a week or two I should have installed 4.56 instead. 4.10 is ok if all you want to do is cruise the streets but 4.56 is even better for that. For offroad,

4.10 is too high of a ratio and 4.56 is a far better ratio.

When I went to 35" tires, I jumped to 4.88 with no regrets... 35" tires and

4.88 is a superb all-around ratio for a 5-speed equipped Jeep. 4.56 would be "ok" for 35" but it's the same deal with 4.10 with 33" tires... both are too low of a ratio, the next lower ratio raises your engine rpms just enough to make driving a pleasure instead of a constant 'downshifting' battle. I'd go for 4.56 for 33" tires if I were doing it again, that is for sure.

Jerry

Reply to
Jerry Bransford

Reply to
L.W.(ßill)

Reply to
L.W.(ßill)

Yeah, my wife's FJ-40 has something like that, and it doesn't even have over drive!

Earle

Reply to
Earle Horton

My preference is the lower gearing - I'm running 5.13s with 35s and have no complaints. The 4.0L (and 258) responds well with this combination. Last time I checked, in 5th she pushes around 2500rpms @ 65-70mph. In a modified SWB Jeep, I have no desire to go much faster than that anyway. I chose the

5.13s because it gives the flexibility of stepping up to 37s or larger (I almost went with the 5.38s).

What most agree upon:

4.10 - 4.88 for 33s 4.56 - 5.13 for 35s 4.88 - 5.38 for 37s

Terry.

92YJ

Reply to
Terry Jeffrey

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