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colo dean
11-13-2015, 08:45 PM
So I am a little confused planning future upgrades and the when and where's. The basic info: 14 JK Sport, 2d, automatic.
The plan: (granted this will take a while)
37's
Evo bolt on coil overs front and rear
D60 front and rear.
And other needed changes for this.

Building to crawl over rocks as well as daily driving.

The question is in axle assemblies. I see for the rear there is the Currie Rockjock minus r/p for approx 2k, Dana ultimate 60 that looks like it comes with either 4.88 or 5.38 gears for a little over 4k and in the middle the Teraflex CDR60 4.56 - 5.38 gears and ARB locker for 3700 and change. I believe the Teraflex is not US made so not really looking to hard at that one.

I know you get what you pay for, but are there pros or cons to leaning either way between the Dana and the Currie? Knowing the plan is to go to coil overs will that influence what I should be looking at?

Never really messed with axles before so I don't have a good grip on this subject Any other recommendations appreciated. Not dead set on 60's but just figured it would be less likely to break than 44's and want to take the time to build something that I can go play with and not break it. I know a lot of that comes with how you drive and treat your rig. Still pretty much an off road newbie so the experience of when to go and when to back off is still being learned and will sometimes be learned at a cost.

Headed to work shortly, but thanks for your thoughts.

MR.Ty
11-13-2015, 08:58 PM
If you are planning on sticking with 37s, keep your rear and only replace the front with a PR44.

The rear axle weak point are the axle flanges which can be easily replaced.

cozdude
11-13-2015, 09:14 PM
If you are planning on sticking with 37s, keep your rear and only replace the front with a PR44.

The rear axle weak point are the axle flanges which can be easily replaced.

this^ and what I plan on doing with mine.

being that you have a 2 door and you don't plan on going over 37's, im assuming, you can run a pr44 up front and keep your stock rear since it is a true d44 unlike the front. this means you can run 37's on it. as mr.ty stated the weak point is the flange since it is a semi float axle.

colo dean
11-14-2015, 07:23 AM
Thanks for the input guys. Would you recommend moving to chrome/upgraded axles in the rear or just stay with stock and keep a spare? I assume even the upgraded axle will still have the same weak point. Next question. Would you recommend 4.56 or 4.88 with the 37's? I don't think I want to get into the 5's do I?

MR.Ty
11-14-2015, 10:43 AM
Thanks for the input guys. Would you recommend moving to chrome/upgraded axles in the rear or just stay with stock and keep a spare? I assume even the upgraded axle will still have the same weak point. Next question. Would you recommend 4.56 or 4.88 with the 37's? I don't think I want to get into the 5's do I?

When you get a rear locker you'll have to get new shafts because the spline count will change. Run what you have now until you regear it and put a rear locker into it.

I do recommend the 5.13s for 37s. For street use the rpms will be a little high but only about 100 more rpms than 4.88s. That being said, 5.13s in a dana30 means that your front ring and pinion will be small and weak. You should be fine as long as you don't put a locker into the front and if you are easy on the skinny pedal when wheeling. Once you get a PR44 to replace it you should have no worries. :yup:

bcakers83
11-14-2015, 10:53 AM
I have a 2012 rubicon 2 door automatic with 37" tires and with 4.88 Yukon gears from 3.73 gears and I'm about 300-500 rpm higher now at 120 kph , but have way more power and slightly better fuel economy.
If that helps you.

Ddays
11-14-2015, 12:37 PM
FWIW, I did the switch from 4:88's to 5:13's when I upgraded my axles and the difference is noticeable. I second MrTY, I would highly recommend 5:13's over 4:88's. Better acceleration and the difference in gas mileage is negligible. Unless you live in Texas and cruise at 105, you should be just fine.

Also, since you are in the research stage, do yourself a favor and check out Dynatrac's axles. They are #1 for a reason. I have not read good things about Curries customer service, so buyer beware.

Good luck and lets see some pics when you're done!

cozdude
11-14-2015, 02:55 PM
When you get a rear locker you'll have to get new shafts because the spline count will change. Run what you have now until you regear it and put a rear locker into it.

I do recommend the 5.13s for 37s. For street use the rpms will be a little high but only about 100 more rpms than 4.88s. That being said, 5.13s in a dana30 means that your front ring and pinion will be small and weak. You should be fine as long as you don't put a locker into the front and if you are easy on the skinny pedal when wheeling. Once you get a PR44 to replace it you should have no worries. :yup:

You do not have to change your spline count when you get a rear locker. I'm still running stock 30 spline. Since I just got the new revolution axle shafts in this allows me to keep my stock ones and just rebuild the bearings. now I have two trail spares for if I break the revolutions or if someone else breaks a stock shaft.

cozdude
11-14-2015, 02:57 PM
Thanks for the input guys. Would you recommend moving to chrome/upgraded axles in the rear or just stay with stock and keep a spare? I assume even the upgraded axle will still have the same weak point. Next question. Would you recommend 4.56 or 4.88 with the 37's? I don't think I want to get into the 5's do I?

If you keep the stock spline found when you upgrade your locker in the rear you can run the stock shafts till they fail then replace them. Or what you can do is put the new shafts in with your locker and now you can use the stock shafts as spares.

MR.Ty
11-14-2015, 03:21 PM
You do not have to change your spline count when you get a rear locker. I'm still running stock 30 spline. Since I just got the new revolution axle shafts in this allows me to keep my stock ones and just rebuild the bearings. now I have two trail spares for if I break the revolutions or if someone else breaks a stock shaft.

Well shit. I learned something new today.

Sorry for the bad info OP.

colo dean
11-14-2015, 03:55 PM
If you keep the stock spline found when you upgrade your locker in the rear you can run the stock shafts till they fail then replace them. Or what you can do is put the new shafts in with your locker and now you can use the stock shafts as spares.

Since I don't have a locker now, can I get one with the factory spline count? Was looking at the ARB so I thought I'd have to change out the factory shafts. Would be convenient to be able to use factory shafts.

cozdude
11-14-2015, 03:57 PM
Since I don't have a locker now, can I get one with the factory spline count? Was looking at the ARB so I thought I'd have to change out the factory shafts. Would be convenient to be able to use factory shafts.

Yes you can get a 30 spline arb. It's what I run. Ran it with stock shafts for two years and just recently upgraded to revolution chromoly shafts

colo dean
11-14-2015, 05:38 PM
Thanks Coz, will check into that, figure probably be tax time before I can upgrade but trying to get some knowledge so I only spend money once.