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Discussion Starter #1
Stimulus Check Time!!!!!!!

Okay I'm looking to get some new gears since I have added the 35 inch tires and 4 lift. I'm going to be going with 4.56 front and rear. Now my dilemma is if I'm doing both on and off road travel (40 minute commute for work), would it be a smart move to do lockers in front and back or one or the other? Also should I just leave the axles at the stock spline count or invest in some new ones?

I dont want to go wheeling and break an axle. Since installation fees for the gears are so horrible would it be beneficial to do all of this at once or span it out?
 

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Better to do it all at once. A locker in front is not noticeble in 2wd so if you can afford it do both. I don't really see a need to upgrade the axle spline count just for 35's. are you sure 4.56 is enough gearing. 4.88 or 5.13 would be better.
 

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Discussion Starter #4
According to the chart if i went 5.13 i would get to much power and lose mpg. I drive 40 minutes each way to work so I will have to look into 4.88. I'm definately going with the aussie up front, however which rear locker would you suggest???
 

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According to the chart if i went 5.13 i would get to much power and lose mpg. I drive 40 minutes each way to work so I will have to look into 4.88. I'm definately going with the aussie up front, however which rear locker would you suggest???
WoW!, 40 minutes each day both ways, @ $4 a gallon....I feel for you. Times are getting so bad,... Aussie upfront will be great and priced right, some are running OX or ARB for the Rear..
 

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Discussion Starter #6
Hahaha ya tell me about it. At least I'm still averaging 17Mpg with my setup. BFG KM2s are the way to go for highway driving!!!!!!!!!!!

Im looking at the detroit lockers that are around 600, but 900 plus the compressor for the arb's is killing me.
 

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I don't think the ox is available for the jk's yet. 4.88 with the aussie up front and an arb in the rear would be the ticket. You would also get onboard air to fill your tires. Don't worry about spline counts with 35's. You should be fine as long as you don't bounce it.
 

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Discussion Starter #8
NO BOUNCE FOR ME:bounce: I only do mild wheeling so im not an extremist. ( well there was that time I went hood first into a mudpit and flooded my jeep and killed the clutch after making it out) :bawling:

Great times.

However thanks for the info....Time to spend some money!!!!
 

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I just put 35" KM2's on my 08 Rubi 4 dr. I am having 5.13's put in next Tuesday. I thought about 4.88's but decided against it; and I think 4.56's would be a huge mistake and waste of money.

With stock 32's and 4.10's I was doing 2250 at 75 MPH (by GPS). And it came out of Overdrive a lot. The 4.10's would be better with 30" tires.

With my 35's and 4.10's at 75 MPH (again by GPS) and in OD I'm turning 2050 RPM. Except on level ground and with a very light throttle it is virtually impossible to keep it from going into OD frequently.

My calcs indicate that 35's with 5.13's will put my RPM at 2550 at 75 MPH. I think this extra 300 RPM over 32's and 4.10's will make it much more driveable on the freeway, keeping it out of OD on all but good hills, make the cruise control work much better (it doesn't work worth a damn with 32/4.10) and give it a much peppier feel both on and off road. Myunderstanding is that the sweet spot on this engine for power and mileage is 2400 to 2700. 5.13's put you right in the middle of this with 35's. I think if 37's are a possibility 5.38's would be the way to go.

4.88's would be better than stock or 4.56's but I'd go with the 5.13's. I haven't spoke to anyone with 5.13's that is unhappy with them. Those I've spoke to that did 4.88's wwish they had done 5.13's.

As to the lockers do them now. I'd probably do ARB front and rear.
 

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Discussion Starter #10
Thanks for the reply and ya im looking more for the 5.13's however remember price is a concern here. **** Im 21 and have a decent job but I dont have an overabundance of funds for all my jk needs. I have heard nothing but good things from the aussie up front plus there is a whole write up on the install so that saves me money. Probably will be putting the ARB into the rear. I like the whole compressor thing for when I need to air up tires.
 

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Thanks for the reply and ya im looking more for the 5.13's however remember price is a concern here. **** Im 21 and have a decent job but I dont have an overabundance of funds for all my jk needs. I have heard nothing but good things from the aussie up front plus there is a whole write up on the install so that saves me money. Probably will be putting the ARB into the rear. I like the whole compressor thing for when I need to air up tires.
What manufacturer are you going with?
 

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Discussion Starter #12
For the gears I'm going with superior. What would you suggest?
 

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I will echo what others said. 4.56 was a good choice for the 4.0. This engines lives at a slightly higher rpm. 4.88's now are about what 4.56's where with the 4.0. I had a x model with the tiny tires and 4.10's. When you do the math, with 35's, it comes out to just a smidge under 4.88 so that is the gear that will return you to stock ratios with 35's. 5.13's if you wanna go deeper then what it was stock and for larger tires.

I locked just the front. in the past i have locked the rear first. I am a true beliver of locking the front if you are only gonna do one. Of course, it would be nice to do both but the wallet will be the judge of that one, lol :beer:


like you said, it is an easy install you can do yourself, just be sure you have a good bench vise for removing, installing ring gear bolts, lol. I didn't, had a impact gun to get them off but getting back on was a pain. A good vice will make it an easy one person job

http://www.jkowners.com/forum/showthread.php?t=1906
 

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Discussion Starter #14
I will echo what others said. 4.56 was a good choice for the 4.0. This engines lives at a slightly higher rpm. 4.88's now are about what 4.56's where with the 4.0. I had a x model with the tiny tires and 4.10's. When you do the math, with 35's, it comes out to just a smidge under 4.88 so that is the gear that will return you to stock ratios with 35's. 5.13's if you wanna go deeper then what it was stock and for larger tires.

I locked just the front. in the past i have locked the rear first. I am a true beliver of locking the front if you are only gonna do one. Of course, it would be nice to do both but the wallet will be the judge of that one, lol :beer:


like you said, it is an easy install you can do yourself, just be sure you have a good bench vise for removing, installing ring gear bolts, lol. I didn't, had a impact gun to get them off but getting back on was a pain. A good vice will make it an easy one person job

http://www.jkowners.com/forum/showthread.php?t=1906

Thanks WTF LOL I'm going to get the 5.13's and definately lock that front. Thanks for giving me the link to the write up thread.
 

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If you decide on the axle shafts at the same time, don't worry so much about changing the spline count. Look at some chromalloy(?) shafts instead.
 

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I don't think the ox is available for the jk's yet. 4.88 with the aussie up front and an arb in the rear would be the ticket. You would also get onboard air to fill your tires. Don't worry about spline counts with 35's. You should be fine as long as you don't bounce it.
Just thought I would chime in on this. The JK's D30 is out in both the 27 and 30 spline. The D44 30 spline rear is ready in a week and the 35 spline is a month out. The air actuator kits are ready, and the electric actuator is in the final stages of development. Very good time to be OX!

Please email me with specific questions.
[email protected]
 

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I thought the Dana 30 was a 27 spline on the 4door Unlimited? I've read that it's also 27 on one side and 32 on the other so how does the locker handle this as that gave me the instant BS signal when I read it. Does anyone have a shop manual to find the real count for the Dana 30 on the JK.

How much is the electric OX for the dana 30? I'm switching from 4.11 to 4.88 (have a 6 spd) in August and I'm collecting all the parts now.
 

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I thought the Dana 30 was a 27 spline on the 4door Unlimited? I've read that it's also 27 on one side and 32 on the other so how does the locker handle this as that gave me the instant BS signal when I read it. Does anyone have a shop manual to find the real count for the Dana 30 on the JK.

How much is the electric OX for the dana 30? I'm switching from 4.11 to 4.88 (have a 6 spd) in August and I'm collecting all the parts now.
the D30 is stock with 27 splines, you can upgrade them to 30 splines.
 
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