Setting up a JKU

StG58

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Ok, first off, I'm aware that this is a TJ forum. There's also some very knowledgeable people here whose advice I trust.

The wife has a 2012 JKU Sport. Automatic. What are the recommended companies to look at for:
Lifts
Wheels
Bumpers
Body armor
Skid plates
Rock sliders
Programmers
Anything else?

Her JKU is NOT going to be taken out by a parking lot pole again.

It's natural habitat will be FS roads and the more open skid trails in the PNW. Probably about halfway between what the TJ does and what the Suburban does.
 
Savvy and Currie still apply to the JKs in terms of building high quality products, but I'm sure you already know that.
 
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Savvy and Currie still apply to the JKs in terms of building high quality products, but I'm sure you already know that.
Yup, but I don't even know what all is involved in setting up a JKU. 35" tires? Bigger? It's got 33's on it now. 3" lift? Taller? When do I start running into issues?

I've crawled around under the wife's JKU. It's not going anyplace without additional skids and protection. Who's?

Bumpers and rock rails...not Shittybuilt, but who has quality stuff that works.

It's like a TJ, but not the same. Not close.

Most of the JK forums are all about light bars, angry eyes and stereos.
 
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So it sounds like perhaps setting up the JK isn’t as easy as we thought? I always figured you just put a 3” lift on, some 33” tires, a winch, some bumpers and call it a day.

Then again, I’ve also never crawled under a JK. Do these things need SYEs and CV driveshafts like our TJs do?
 
So it sounds like perhaps setting up the JK isn’t as easy as we thought? I always figured you just put a 3” lift on, some 33” tires, a winch, some bumpers and call it a day.

Then again, I’ve also never crawled under a JK. Do these things need SYEs and CV driveshafts like our TJs do?
You can put 33's on a stock JK. They fit nicely. The rear drive shaft on a JKU is long, so I don't really know. I've read that the front drive shaft is problematic, but again, I don't know. It's got mid arms from the factory. They look stout. Stout enough? Just lots of undiscovered territory here.
 
Interesting, I would like to know as well. The JKs get rated by all the magazines as being very capable in stock form, which is what makes me think you could just throw some 33” tires on, a small lift, and be highly capable just like that.
 
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From what I was told, depending on the backspacing, you can fit 33x10.5 on a stock suspension.

With a 2” lift, you can fit 35’s.

But that’s as much as I know.

As for brands/manufacturers, I would just stick with the guys that make quality parts for the TJ’s. I can’t see them “cheaping out” on JK/U stuff.
 
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Same companies
Stock 33
2-2.5 Lift 35
 
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JKU is a different sience as the TJ. Is the popular model and is tons of still supported products for them.

A Friend of mine went with Rubicon Expres 3.5 long arm lift, Rock Hard skids plates and Cooper SST 37" he regear to 5.13(must do?) via dealershirp due the warranty. Have to mention, this guy and GenRight local rep wheel and ride bikes together...

This Jeep handle awesome in and off road but it use maybe more forest roads around Tennesse.

Keep on mind that JK are quite sensitive to the trany temp, once you add underarmor you may want to add an auxiliary trany cooler to avoid the infamous Oil Temp warning light.

Look for a company called Rubitrux.

Let see what else i recal later.

Oh, do your homework on the programers. Once you use it on your JK can't be used on any other.
 
3.5 metalcloak gamechanger rock sport edition rides great. She's on 37 ko'2, again rides and drives great. Metalcloaks rear tire carrier bumper is great, no rattles, I'm not sold on the front bumper. 4.88 gearing with the 6 speed is s good setup, but she doesn't do to much freeway. Front drive shaft left us at about 5000 miles into the lift. Hope this helps!

IMG_1686.JPG
 
JKU's do not need as much of a lift as TJ's do. I have a friend who ran the Rock Krawler mid arm 3.5" lift and ran 37's.
To run 35's a 2.5" lift should be enough. The issue with tires like 33's is the back spacing of the OEM wheels.

Stock tire options:
1. 225/75/16 (29”x9”)
2. 255/75/17 (32”x10”)
3. 255/70/18 (32”x10”).

I followed this post from that other forum as a guide for my wife's JKU with no lift.

I went with tires that were on the 33x11 range (285/75/16, 285/70/17 or 275/70/18) I have to take a look to see which one I have on there. I had to put in some wheel spacers to correct the backspacing rubbing on front swaybar on tight turns. I went with wheel spacers because my wife has yet to make up her mind on what wheel she wants LOL
 
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Thanks folks! Good stuff here so far.

Right after we got her rig we put tires and wheels on it. 285/75R16's, KO2's. No rub. @JeepNWilly, my wife did the same exact thing on the wheels. Couldn't make up her mind. So, she got cheap ones until she does.
 
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Around 3in of lift on a JK you need to address the exhaust as well, I seem to recall it has a funny bend that needs extended. Terraflex makes a good 2.5 in kit that would let you run 35s easily.
 
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I don't own one, but I have jeep buddies that do, and I helped one of them install a Metal Cloak 2.5" lift on his JKU. A few issues I noticed after the lift,
1. the front driveshaft boot will rub against the exhaust crossover tube at droop. There is a company, can't remember which, that makes spacers to move the crossover tube back. Other option is get u-joint style new drive shaft.
2. The evap canister hits the rear driveshaft boot and rips it. Easy fix to relocate the canister back an inch.
3. The front portion of the pinchweld on the rear wheel well gets close with anything bigger than 33's. Proper bumbstops or adjustable CA's will help with clearance. Some trim the pinchweld seam for clearance.
As far as brands of stuff, JCR Offroad makes some nice bumpers/armor for the JKU. AEV and Metal Cloak have a strong JK presence. Of course we all know Currie/Savvy has good stuff.
 
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Out-bloody-standing! This is what I'm talking about. It's these little "gotcha's" that are useful to me. Keep'm coming...we may be building a 2012 JKU on the Forum!
 
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Ok, first off, I'm aware that this is a TJ forum. There's also some very knowledgeable people here whose advice I trust.

The wife has a 2012 JKU Sport. Automatic. What are the recommended companies to look at for:
Lifts
Wheels
Bumpers
Body armor
Skid plates
Rock sliders
Programmers
Anything else?

Her JKU is NOT going to be taken out by a parking lot pole again.

It's natural habitat will be FS roads and the more open skid trails in the PNW. Probably about halfway between what the TJ does and what the Suburban does.
I can only go off of my 2007 Rubicon, which wasn't an Unlimited, but a lot of the mods you are looking at will work on either.

What I did on mine was an OME lift; JKS adjustable track bars front and rear; PPM-8002 Synergy Suspension Jeep JK Heat Treated Tie Rod (best mod of the bunch); 285/75-17 BFG KM2; I had AEV Pintler wheels for a while, but went back to the stock Moabs; I had added outrigger bars to the oem Rubicon rock rails (my welding skills suck, but it came out great anyway) which they sell now as stock units;

On the 2012 JK Sport I had, I did the same suspension modification, but did not go with the same tires.

I also have an AEV ProCal
https://www.morris4x4center.com/aev...GNOvj0Gbbik-ADMwhBhoCkeAQAvD_BwE&gclsrc=aw.ds that I bought for my automatic 2012 Sport. When I sold the JK, I put the programming back to stock, so the ProCal would work on another JK. If you want, I can send it to you to try out. If it works on your wife's JKU, great, make an offer at that point if you want it...I could also send it up to sunny :) Oregon next month when my daughter and son-in-law return to Portland from the Thanksgiving holiday...
 
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I can only go off of my 2007 Rubicon, which wasn't an Unlimited, but a lot of the mods you are looking at will work on either.

What I did on mine was an OME lift; JKS adjustable track bars front and rear; PPM-8002 Synergy Suspension Jeep JK Heat Treated Tie Rod (best mod of the bunch); 285/75-17 BFG KM2; I had AEV Pintler wheels for a while, but went back to the stock Moabs; I had added outrigger bars to the oem Rubicon rock rails (my welding skills suck, but it came out great anyway) which they sell now as stock units;

On the 2012 JK Sport I had, I did the same suspension modification, but did not go with the same tires.

I also have an AEV ProCal
https://www.morris4x4center.com/aev...GNOvj0Gbbik-ADMwhBhoCkeAQAvD_BwE&gclsrc=aw.ds that I bought for my automatic 2012 Sport. When I sold the JK, I put the programming back to stock, so the ProCal would work on another JK. If you want, I can send it to you to try out. If it works on your wife's JKU, great, make an offer at that point if you want it...I could also send it up to sunny :) Oregon next month when my daughter and son-in-law return to Portland from the Thanksgiving holiday...
That is an outstanding and generous offer. Thank you. I'll PM later.