Another Re-gearing Thread...Help Me Out.

blask06 said:

So I've spent quite a bit of time searching online and the forum. Seems to be a pretty even split on what people recommend. I am hoping to get some opinoins from some people with real life experience, so here it goes. I have 2011 Rubicon Unlimited, auto, w 35" tires (34.5") and the stock 4.10 gears. I'm also at 5200' - 6300' altitude if that matters and I have no intention of going to a larger tire size. I do a lot of highway diriving, about 70+ miles a day. I recently put on a supercharger and I can really notice that the gearing is off now. I've narrowed it down to 5.13 or 5.38 gears. Anybody have any input? Driving performance? MPG? Anything else? And yes, I've seen "the chart". Thanks.

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Canvas JK said:

I have not regard but will re-gear to 4.88 for 35's or I may just jump up to 5.13 to run 37's.

Here is a thread that shows what gears goes with what tires you are going to run.

http://wayalife.com/showthread.php?16881-Gear-ratio-for-37s&highlight=gear+chart

R/
Will

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blask06 said:

Thanks. Seems like in that thread the concensus is 5.13. I have the 3.8l though.

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Speeddmn said:

With the 3.8L and 35's and an auto and plans to go higher I would use 5.13's. The 5.38's as previously mentioned in numerous posts/topics are to small. Meaning the pinion (shaft/gear) is to small in diameter to handle the stress of the tires/power (since you mentioned a supercharger) and use off road. Also as you are in Colorado the 35's, even with added power, will struggle when headed thru the mountains.

The 5.13's will also allow you to run a 37 inch tire in the future if your plans ever change. Better to re-gear once then twice.

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cozdude said:

from a man running 5.13's and 35's I would say go that route. I love the performance out of them. mpg is the same as what I was seeing with 3.73 gears and 35's (13 city and 17 highway). plenty of power thru the hills of PA.

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Brankz said:

Can you run 4.88s with 37s?
I another thread lots of people say no to run 5.13s on a Dana 30 correct?

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2013rubirick said:

With a Dana 30 you really shouldn't go over 4.88 because the pinion gear will be really small.

Sent from my SAMSUNG-SM-N910A using WAYALIFE mobile app

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Brankz said:

So 4.88 will be the max that I can go? Yup 10/4

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10frank9 said:

5.13's in a D30? Your axles haven't imploded yet? :shock:

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blask06 said:

So I've spent quite a bit of time searching online and the forum. Seems to be a pretty even split on what people recommend. I am hoping to get some opinoins from some people with real life experience, so here it goes. I have 2011 Rubicon Unlimited, auto, w 35" tires (34.5") and the stock 4.10 gears. I'm also at 5200' - 6300' altitude if that matters and I have no intention of going to a larger tire size. I do a lot of highway diriving, about 70+ miles a day. I recently put on a supercharger and I can really notice that the gearing is off now. I've narrowed it down to 5.13 or 5.38 gears. Anybody have any input? Driving performance? MPG? Anything else? And yes, I've seen "the chart". Thanks.

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blask06 said:

So anymore input on this?

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blask06 said:

Sounds like 5.13s are the way to go. Anyone know of any good shops around northern Colorado. Don't think I'm going to DIY this one.

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hbkid22 said:

Where in CO? And I would say go to Northridge 4x4 in Longmont otherwIse there are plenty of other shops in boulder and golden.

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blask06 said:

I'm up in Fort Collins. Longmont wouldn't be too bad.

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