Mods for 2011 JK Rubicon, 37s, etc
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JK Newbie
Joined: Aug 2010
Posts: 77
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From: Rochester, NY
Mods for 2011 JK Rubicon, 37s, etc
Hey everyone, since I'm new to the JK and I've had some trouble searching...
I'd like to do 37's, so I called up Rock Krawler yesterday and they recommended their 3.5" Mid-Arm kit. I'm thinking about getting the pro one to get the aluminum, but not sure if its necessary, your thoughts?
I also need to know what other supporting mods I will need to make this a reliable daily driver on 37's. Flat fenders? 4.88's or 5.13's? Superchips/exhaust/intake?
I really just want to get a budget together for building up the Jeep since I'll be using it for some promotion for one of my businesses.
Thanks!
I'd like to do 37's, so I called up Rock Krawler yesterday and they recommended their 3.5" Mid-Arm kit. I'm thinking about getting the pro one to get the aluminum, but not sure if its necessary, your thoughts?
I also need to know what other supporting mods I will need to make this a reliable daily driver on 37's. Flat fenders? 4.88's or 5.13's? Superchips/exhaust/intake?
I really just want to get a budget together for building up the Jeep since I'll be using it for some promotion for one of my businesses.
Thanks!
Thread Starter
JK Newbie
Joined: Aug 2010
Posts: 77
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From: Rochester, NY
Make sure to do your homework...
Are you in an Unlimited or 2 door?
If you are in an Unlimited, once you go over 2.5" in lift you will need to look at a new drive shaft.
I'm running 35's with chopped fenders and no bump stops with minor rubbing just to give you a little basis on what you can do.
Wait for the Rugged Ridge snorkel kit...I think this is going to be a top seller when they come out with it. With 37s I think the generally consensus will be to go with 5.38s. If you want better gas mileage go with 5.13s. Save you some money on exhaust, buy a muffler and have a shop weld it up for you...no sense in wasting so much money on a kit. There are more programmer choices than Superchips...I've heard good things about the Diablo tuner.
Oh and welcome to the forum and I see you already got the bug
Are you in an Unlimited or 2 door?
If you are in an Unlimited, once you go over 2.5" in lift you will need to look at a new drive shaft.
I'm running 35's with chopped fenders and no bump stops with minor rubbing just to give you a little basis on what you can do.
Wait for the Rugged Ridge snorkel kit...I think this is going to be a top seller when they come out with it. With 37s I think the generally consensus will be to go with 5.38s. If you want better gas mileage go with 5.13s. Save you some money on exhaust, buy a muffler and have a shop weld it up for you...no sense in wasting so much money on a kit. There are more programmer choices than Superchips...I've heard good things about the Diablo tuner.
Oh and welcome to the forum and I see you already got the bug
I think I'd go with the 5.13's for a little better gas mileage, but I don't want the Jeep to be a dog goin up hills or bombing around town. I'll have to look at the diablo tuner as well. I just got one of the latest magazines and it had all of the tuners in it. Looked like you could do a lot with the Superchips.
I can't wait to get it! I'll have to slowly start accumulating parts before I pick it up at the end of the month haha.
JK Super Freak
Joined: Mar 2010
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From: Next To You
You want have to get driveshafts for the unlimited with 2.5" lift, thats only if you go more than 4" that you'll have to install new DS. You'll be OK with the 4dr on a 3.5" or 4" with the stock DS.
On gears everything depends on if your getting an Auto or Manual trans. Auto trans I would go with 5.13"s, if your getting a Rubicon model I would go with 5.38's. On a Manual some people say you need to go with 4.88's.
If you want to use my Jeep as a billboard for your business we could work something out with some mods.
On gears everything depends on if your getting an Auto or Manual trans. Auto trans I would go with 5.13"s, if your getting a Rubicon model I would go with 5.38's. On a Manual some people say you need to go with 4.88's.
If you want to use my Jeep as a billboard for your business we could work something out with some mods.
Last edited by jeepoholic; Sep 4, 2010 at 03:45 PM.
JK Super Freak
Joined: Mar 2010
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From: Next To You
The Rubis come with D44 front ends which means you can fit 5.38's where as a Sahara or X models only have D30 which means the lowest gear that will fit is a 5.13.
Last edited by jeepoholic; Sep 4, 2010 at 04:27 PM.
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JK Enthusiast
Joined: Feb 2010
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From: Plover, WI & Benson, AZ
Keep in mind that as soon as you start modifying with a lift, tires, and gears your mpg will go down. My biggest drop was when I went from 4.10 to 5.13 gears. Total drop was from 19 when stock to 14.5-15 after the mods. That doesn't mean you shouldn't do it. All Jeeps need some mods. Do your research, take your time and don't jump in before you have all of the pros and cons of a particular mod. I suggest that you drive it awhile before you modify. There is a lot of good info available on this forum, but only a few are experts. Study the posts and figure out who has the best advise. ........... Have fun
JK Enthusiast
Joined: May 2009
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From: Marana, AZ
Hey everyone, since I'm new to the JK and I've had some trouble searching...
I'd like to do 37's, so I called up Rock Krawler yesterday and they recommended their 3.5" Mid-Arm kit. I'm thinking about getting the pro one to get the aluminum, but not sure if its necessary, your thoughts?
I also need to know what other supporting mods I will need to make this a reliable daily driver on 37's. Flat fenders? 4.88's or 5.13's? Superchips/exhaust/intake?
I really just want to get a budget together for building up the Jeep since I'll be using it for some promotion for one of my businesses.
Thanks!
I'd like to do 37's, so I called up Rock Krawler yesterday and they recommended their 3.5" Mid-Arm kit. I'm thinking about getting the pro one to get the aluminum, but not sure if its necessary, your thoughts?
I also need to know what other supporting mods I will need to make this a reliable daily driver on 37's. Flat fenders? 4.88's or 5.13's? Superchips/exhaust/intake?
I really just want to get a budget together for building up the Jeep since I'll be using it for some promotion for one of my businesses.
Thanks!
For gears, 5.38 with a Rubi Auto.
My RK 3.5 X Factor is in transit. Plan on 37 KM2s. I am going to see how they fit without doing anything else. I did just get a 1" body lift and if I need more room to clear the fenders, I will install that. I am not a fan of flat fenders.
From my research and what RK said, drive shafts on an unlimited should be okay; at least for a while. I expect I will have to replace them sooner or later, but not immediately - guess I will see.
Probably going to run the stock wheels with with Spidertrax 1.5" spacers.
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JK Freak
Joined: Dec 2009
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From: Keene, New Hampshire, United States
I'm in for a similar setup as well, but going with 3.5 x factor plus long arm kit. the KM2's are an option for me because they are so light but they are closer to 36.5 I believe whereas the Toyo's and Procomps measure a true 37. I would just go to the 38's in the KM2's which measure 37.5 but they are approx 50% more in price for an extra inch? F'd up if you ask me so I'll probably just go with the Toyo 37x13.5 17 which is one of the best looking tires ive seen and seems to be a perfect fit for the lifted unlimiteds.
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I'm in for a similar setup as well, but going with 3.5 x factor plus long arm kit. the KM2's are an option for me because they are so light but they are closer to 36.5 I believe whereas the Toyo's and Procomps measure a true 37. I would just go to the 38's in the KM2's which measure 37.5 but they are approx 50% more in price for an extra inch? F'd up if you ask me
2 cents.
Thread Starter
JK Newbie
Joined: Aug 2010
Posts: 77
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From: Rochester, NY
I ordered a 6spd, so I guess I'll be ok with the 5.13's 
From what I've been reading, I can run the stock driveshafts for a little while before upgrading. I want to do things in stages, so I'm hoping I can do lift and wheels/tires first, but obviously be limited on any wheeling.
Also, if it makes a difference... RK said the midarm kit relocates the rear axle so you don't have to modify the pinch seam.
From what I've been reading, I can run the stock driveshafts for a little while before upgrading. I want to do things in stages, so I'm hoping I can do lift and wheels/tires first, but obviously be limited on any wheeling.Also, if it makes a difference... RK said the midarm kit relocates the rear axle so you don't have to modify the pinch seam.