Anybody running 31's with a 3.07? -
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post #1 of 8 Old 06-04-2002, 05:29 PM Thread Starter
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Anybody running 31's with a 3.07?

I've got a 6 cyl. w/ a 5 speed and a stock 3.07 axle. I'm wanting to move up to a set of 31x10.50's and wonder how this will effect hwy. driving. I'm a flatlander, but may occasionally take it up to the mountains. Right now, in 4th gear, she runs at about 2250 rpm. Has anyone with this axle made this change? Is it worth the expense to regear if I'm going to stay with 31's for a while?

Thanks for all the help.


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post #2 of 8 Old 06-04-2002, 05:57 PM
Dan Morera
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I have 31"s with 3.07 and it's not that bad. But I'll bet it will be nice to regear. Maybe in a couple of months.

Don't rush it. I live in a place with alot of mountains and no mayor problem.

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post #3 of 8 Old 06-04-2002, 08:21 PM
Bob K
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Agree with Dan. Power is still more than adequate if your engine is running properly. I wish my gears were lower, particularly on the highway when I have to downshift for long hills or acceleration. Regearing is about $1000 parts & labor. I don't think it's worth the $$. Some might feel differently.

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post #4 of 8 Old 06-04-2002, 10:24 PM
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I have 32's with 3.07's and with a modified aribox k&n and no restrictor its not too bad but when i bought it it had 31's on it and i had no problems even got it to do 100 a couple of times don't waste the money on a regear, if you want do some small engine stuff (intake maybe exhaust) and you'll be fine

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post #5 of 8 Old 06-05-2002, 10:44 AM
Prime Lord
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Question for you guys w/ 31's and 3.07's.....what do you get for gas mileage?? I'm gonna be running like that shortly & want to know what to expect.


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post #6 of 8 Old 06-05-2002, 11:39 AM
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I am running 31's and 3.07 gears. They are not that bad on the street, but off-road the better gears are needed.
The gas milage is about 225-280, depending on how much city driving I do.

Eople may say that you do not need to re-gear. If yo uare never planning ot go off-roadm then they are correct. But when I go off-road, going up hill or up rocks and such, 3.07' suck. You end up using a lot of clutch, which burns them out. My $.02 is to save your money for a few months and do the re-gear. You will definately notice the difference on the trails and on the highway.

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post #7 of 8 Old 06-06-2002, 12:53 AM
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i recently put 31's on my 3.07s.. mileage is for crap.. i'm gonna do 3.73's to handle the 32-33's i'm eventually putting on the rig, as well as cat back exhaust and MSD ignition.. should bring the power and mileage back up from the low teens back to the high teens/low twenties.. check out the latest edition of JP (july 2002) there's a wrangler in there w/ 31's and 3.73's getting about 22mpg

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So he wants to go OFF-ROAD does he????

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post #8 of 8 Old 06-06-2002, 01:12 AM
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well I got about 24 MPG running 32's with 3.55 gears. That was in the mountians of montana where the air/fuel mixture is leaner. back down here at sea level, I get about 17-18, but have much more power.

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