Kickin the tires on a JKU - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > JK Wrangler Technical Forum > Kickin the tires on a JKU

XT (ExtremeTerrain.com) has Barricade Off-Road Armor!ROCKRIDGE4WD Introduces a NEW Jeep Wrangler JK *led* tail Nitro Gear Packages Now Available at Rockridge 4wd

Reply
Unread 04-09-2015, 09:15 AM   #1
FreeJersey
Registered User
2014 WK 
 
Join Date: May 2014
Location: Old Bridge, NJ
Posts: 199
Kickin the tires on a JKU

I traded in my '07 Ram last May for a '14 Grand Cherokee. It's a great ride, and I love almost everything about it. The thing is, I actually miss the bumpier ride of my pick ups (had a Siverado before the Ram). I have been toying with the idea of taking the WK2 back and getting into a JKU.

I have been reading here and on other forums and there is just so much info out there that it's mind blowing. Lifts, gear, etc.

What I want to do is get a set of 35's, most likely GY Duratracs, possibly Toyo MT's. Looking for the least amount of lift to safely run these tires. Sadly, most of my driving is on the highway with some mild weekend dirt and sand trails. That of course is where the gears come in. What I need to know is, would the Sahara with 3.73's be ok for my purpose or should I go with a Rubi with the 4.10's? The local dealers are flooded with Sahara's and Rubi's are few and far between. So, I can most likely get my best deal on a Sahara.

Questions I need answered:

Least amount of lift for 35's?

Best gears for mainly highway use (mileage) for the 35's?

FreeJersey is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 09:36 AM   #2
yoyoyo109
Registered User
2015 JK Wrangler 
 
Join Date: Jun 2010
Location: Houston
Posts: 203
http://www.tnjeeps.com/uploads/galle..._46_253610.jpg

stay in the green.

If you aren't trimming flares, 3.5" should do it
yoyoyo109 is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 09:50 AM   #3
yoyoyo109
Registered User
2015 JK Wrangler 
 
Join Date: Jun 2010
Location: Houston
Posts: 203
To add a follow up, I would recommend going Rubi to start with the 4.10's

While adding a lift might void your suspension, leaving stock gears in there shouldn't void any axle failure. You would want to confirm that in writing with the dealership though
yoyoyo109 is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 10:00 AM   #4
Z-OR
Registered User
 
Join Date: Feb 2015
Location: Sisters, OR
Posts: 23
You, my friend, have a lot going on.

Let's first agree that 35" tires really want new wheels with about 4.5" offset to clear side to side. Somebody will be along shortly to say that you can run wheelspacers too, and they would be correct.

Next step is up and down clearance. A 35" tire needs about a 3" bumpstop extension (front and rear) so as not bash the flares.

Everything beyond that is up to you and your wallet.

There is never a consensus in the Jeep world. But a high quality 2.5" coil lift from one of the major manufacturers, with adjustable upper or lower control arms, and quality shocks (such as Bilstein) is a common theme among happy owners.

I am not going to wade in anywhere near the gear ratio debate. Way too much dick swinging going on. I will say that I run 4.56's on a street and trail driven manual and am very happy.

Best of luck in your JK endevour. You will love it.
__________________
2015 JK 2-dr
2.5" Rock Krawler suspension / RRD Shocks
Crawler Conceptz
AEV ProCal / VKS sliders
Z-OR is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 10:07 AM   #5
yoyoyo109
Registered User
2015 JK Wrangler 
 
Join Date: Jun 2010
Location: Houston
Posts: 203
Quote:
Originally Posted by Z-OR View Post
You, my friend, have a lot going on.

Let's first agree that 35" tires really want new wheels with about 4.5" offset to clear side to side. Somebody will be along shortly to say that you can run wheelspacers too, and they would be correct.

Next step is up and down clearance. A 35" tire needs about a 3" bumpstop extension (front and rear) so as not bash the flares.

Everything beyond that is up to you and your wallet.

There is never a consensus in the Jeep world. But a high quality 2.5" coil lift from one of the major manufacturers, with adjustable upper or lower control arms, and quality shocks (such as Bilstein) is a common theme among happy owners.

I am not going to wade in anywhere near the gear ratio debate. Way too much dick swinging going on. I will say that I run 4.56's on a street and trail driven manual and am very happy.

Best of luck in your JK endevour. You will love it.
What is your hwy mpg? I assume you're on 35's correct?
yoyoyo109 is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 11:05 AM   #6
Z-OR
Registered User
 
Join Date: Feb 2015
Location: Sisters, OR
Posts: 23
Quote:
Originally Posted by yoyoyo109 View Post
What is your hwy mpg? I assume you're on 35's correct?
Wanted to do you the courtesy of a reply. But unfortunately, I can't give you an accurate answer.

Yes, I am on 35's. The Jeep is still in its break in period (<3k miles) and I have never had an opportunity to do a true highway check. I anticipate ending up somewhere in the mid to high-teens for mixed use.

Please know that (generally speaking) highway mileage is more a function of aerodynamics than gearing. Energy required to overcome drag increases exponentially as a function of speed. The Jeep is a brick. Large tires and lift make it even more so.

Short question. Long answer. Slow day at work.

:-)
__________________
2015 JK 2-dr
2.5" Rock Krawler suspension / RRD Shocks
Crawler Conceptz
AEV ProCal / VKS sliders
Z-OR is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 11:11 AM   #7
FreeJersey
Registered User
2014 WK 
 
Join Date: May 2014
Location: Old Bridge, NJ
Posts: 199
Quote:
Originally Posted by yoyoyo109 View Post
http://www.tnjeeps.com/uploads/galle..._46_253610.jpg

stay in the green.

If you aren't trimming flares, 3.5" should do it
Thanks, I have seen that. Funny how they come stock in the yellow. I figured starting with a Rubi with 4.10's would be best, but like I said, not many around, plenty of Saharas though.
FreeJersey is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 11:12 AM   #8
yoyoyo109
Registered User
2015 JK Wrangler 
 
Join Date: Jun 2010
Location: Houston
Posts: 203
Quote:
Originally Posted by Z-OR View Post
Wanted to do you the courtesy of a reply. But unfortunately, I can't give you an accurate answer.

Yes, I am on 35's. The Jeep is still in its break in period (<3k miles) and I have never had an opportunity to do a true highway check. I anticipate ending up somewhere in the mid to high-teens for mixed use.

Please know that (generally speaking) highway mileage is more a function of aerodynamics than gearing. Energy required to overcome drag increases exponentially as a function of speed. The Jeep is a brick. Large tires and lift make it even more so.

Short question. Long answer. Slow day at work.

:-)
That's a good point. I suppose a better question for me to ask is what are your 6th gear rpm's going 70?
yoyoyo109 is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 11:20 AM   #9
FreeJersey
Registered User
2014 WK 
 
Join Date: May 2014
Location: Old Bridge, NJ
Posts: 199
Quote:
Originally Posted by Z-OR View Post
You, my friend, have a lot going on.

Let's first agree that 35" tires really want new wheels with about 4.5" offset to clear side to side. Somebody will be along shortly to say that you can run wheelspacers too, and they would be correct.

Next step is up and down clearance. A 35" tire needs about a 3" bumpstop extension (front and rear) so as not bash the flares.

Everything beyond that is up to you and your wallet.

There is never a consensus in the Jeep world. But a high quality 2.5" coil lift from one of the major manufacturers, with adjustable upper or lower control arms, and quality shocks (such as Bilstein) is a common theme among happy owners.

I am not going to wade in anywhere near the gear ratio debate. Way too much dick swinging going on. I will say that I run 4.56's on a street and trail driven manual and am very happy.

Best of luck in your JK endevour. You will love it.
Thanks, new wheels were definitely part of my plan, not crazy about the stock wheels anyway.

A 2.5" lift should do nicely, I can't go too high, 3 kids and a wife. As long as it gives the clearance, I could probably get away with that.

I don't know why I even asked about gears. Seems that some say they are happy with 3.21's with 35's and others insist that you need 4.88's or even 5.13's.

I'll be at the dealership tomorrow for a suspension issue with the WK2, maybe I'll torture my salesman and see if we can come up with a workable solution.
FreeJersey is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 04:49 PM   #10
jwmbishop
Accidental Obfuscator
 
jwmbishop's Avatar
2011 JK Wrangler 
 
Join Date: May 2011
Location: corsicana, tx
Posts: 4,400
I started at 2.5 lift and added a 3/4 puck at both ends. Like it, so now will get 3.5 springs in her next iteration (and my 5' tall wife decided she's not jeeping so I dont have to accommodate her)... but even at 2.5 it was tall enough to get over most rocks (a bit of turtling) and low enough to get under tree branches.
Yes gears are very subjective. I like the 5.13s but kinda wish I had gone to 5.38 - less throttle to climb steep rocks.
Should point out - not my daily driver! I probably wouldnt like the 5.13s driving every day - my mileage is about 16 combo - best i've seen on hiway is 18 with a tail wind.
__________________
J Wm Bishop EA, ASADE
Classy Chassis Customs. Because the only thing that matters is what's UNDER the dress ...
jwmbishop is offline   Reply With Quote Quick reply to this message
Unread 04-09-2015, 05:08 PM   #11
paul84043
Registered User
2012 JK Wrangler 
 
Join Date: Oct 2010
Posts: 2,701
If you're going for the Auto Transmission, gearing really is not that much of an issue. With the Manual it becomes more critical for crawling. Even at that I ran mine for two years on 35's and stock 3.73's with no problems of any kind. Literally the ONLY time you're going to notice it is if you get into some technical crawling. The increase in power on the other hand is a different issue.
A 2.5" lift and 35's, you will be in great shape. Other mods can wait.

I was getting about 24mpg highway stock, the lift did not change that at all.
After gearing down to 4.56 I lost just over 1 mpg.
My overall rolling average is about 20 right now.
Just came back from Moab pulling a light trailer and even with a gnarly headwind and a canyon both ways, I got 19.5 for the whole trip.
__________________
**
Make a man a fire and you keep him warm for a day....Set a man on fire and you keep him warm for the rest of his life....
**
paul84043 is offline   Reply With Quote Quick reply to this message
Unread 04-10-2015, 01:31 AM   #12
austonreeves
Registered User
1997 TJ Wrangler 
 
Join Date: Nov 2010
Location: Prattville, Alabama
Posts: 1,559
Quote:
Originally Posted by paul84043 View Post
If you're going for the Auto Transmission, gearing really is not that much of an issue. With the Manual it becomes more critical for crawling. Even at that I ran mine for two years on 35's and stock 3.73's with no problems of any kind. Literally the ONLY time you're going to notice it is if you get into some technical crawling. The increase in power on the other hand is a different issue.
A 2.5" lift and 35's, you will be in great shape. Other mods can wait.

I was getting about 24mpg highway stock, the lift did not change that at all.
After gearing down to 4.56 I lost just over 1 mpg.
My overall rolling average is about 20 right now.
Just came back from Moab pulling a light trailer and even with a gnarly headwind and a canyon both ways, I got 19.5 for the whole trip.
Man i must be doing something wrong i got right at 300 to a tank of gas with a 6 speed jku on 265s mixed driving... thats like 14mpg i believe. If i shift around 2500rpms is that 2 high or low? I feel like anything around 2k is too low and bogs down. Im gunna take a guess and say i have the 3.73 gears. Only 99k miles too. My 2 door xj on 235s and a 2 inch lift gets 17 and i drive the piss outta that 4liter
austonreeves is offline   Reply With Quote Quick reply to this message
Unread 04-10-2015, 08:59 AM   #13
Cropduster23
Registered User
2012 JK Wrangler 
 
Join Date: Jun 2012
Location: Wheeler, MI
Posts: 113
2012 JKU with 1.5" leveling kit and 285/70/17 Kelly TSRs. Worst tank average has been 8.6mpg - highway driving directly into a 40-50mph wind. Best tank average has been 22.6mpg - 55mph with very few stop and Gos and a strong tail wind.

Lifetime average over 29k miles is just above 18.4mpg. Mileage seems to be getting better with more miles on the engine. I'm pretty happy with the overall mileage.
Cropduster23 is offline   Reply With Quote Quick reply to this message
Unread 04-10-2015, 09:25 AM   #14
FreeJersey
Registered User
2014 WK 
 
Join Date: May 2014
Location: Old Bridge, NJ
Posts: 199
My local dealer only had 3 Saharas on the lot, all 3 had 3.21 gears. One of them had a 2.5" lift and 35's. Looked great, but not what I'm looking for. They said I would have to order what I want as they never get the 3.73's in and never get Rubicons either, except for special orders. I'll check a few other dealers near by and see what they have to say.
FreeJersey is offline   Reply With Quote Quick reply to this message
Unread 04-10-2015, 02:28 PM   #15
Hudson3
Registered User
2013 JK Wrangler 
 
Join Date: Jun 2014
Location: phoenix, az
Posts: 57
With most of your driving being highway, I would strongly suggest second thinking your decision to trade a '14 WK2 for any year JK.
I speak as the owner of both ('14 Overland Hemi, '13 JK Rubi.).
Judging by the off roading you mention doing, I see no need to spend the premium money a Rubicon commands. I personally did not like 35's with 4.10 gears that the Rubi comes with, so in my experience/opinion that argument is moot. Also, for the off roading you mention, I have a hard time believing the WK2 is not up to the task.
Full size pickups ride much nicer than JKs, so, if by bumpy ride you think you are getting full size truck bumpy, you will be in for a surprise.
I love my JK, I drive to and from work 135 miles a day, so when speaking to highway and JK's I feel pretty confident in speaking the truth.
Anytime my wife has a day off I am elated to swap her WK2 for my JK for the day.
__________________
2013 Rubi 2dr 6spd, 2"BB, MC arms(8), 5.13's, 1310DLs, PSC and Synergy armor.
Hudson3 is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.