Caster adjustment after Rancho lift. - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 09-26-2013, 06:34 PM   #1
Jeeper
 
Join Date: Mar 2012
Posts: 49
Caster adjustment after Rancho lift.

Ok, I put a 3 inch Rancho lift on my 2012 wrangler unlimited. After lift my caster is 2*. I think factory recommends 4* - 4.5*.
I was thinking of getting the Geo correction brackets, which should help, and a set of adj. control arms. Either front upper or front lower.
My question is which ones and do I need the Geo correction brackets.

Firefighter-rn is offline   Quote Quick Reply
Old 09-26-2013, 06:40 PM   #2
Jeeper
 
jadmt's Avatar
 
Join Date: Sep 2012
Location: missoula
Posts: 7,110
I would do the AEV geo brackets as they are only $99 and lots of places have free shipping and try that first. AEV has a forum that covers that info pretty well.

jadmt is offline   Quote Quick Reply
Old 09-26-2013, 07:59 PM   #3
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Rancho has their own drop bracket.

Designed for 3.5 but will work for 2.5-4"

I am at 3.5 and caster is around 4*
Attached Thumbnails
Click image for larger version

Name:	image-574174188.jpg
Views:	44
Size:	181.6 KB
ID:	380921   Click image for larger version

Name:	image-172415322.jpg
Views:	46
Size:	127.4 KB
ID:	380929  

kjeeper10 is online now   Quote Quick Reply
Old 09-26-2013, 08:58 PM   #4
Jeeper
 
Join Date: Mar 2012
Posts: 49
I was thinking of the Rancho Brackets, but do you think I would need Control Arms?
Kjeeper10 what CA are you running - Stock?
Firefighter-rn is offline   Quote Quick Reply
Old 09-26-2013, 09:13 PM   #5
Jeeper
 
Join Date: Aug 2013
Posts: 116
How do you measure/know the caster?
Rightside is offline   Quote Quick Reply
Old 09-26-2013, 09:25 PM   #6
Jeeper
 
jadmt's Avatar
 
Join Date: Sep 2012
Location: missoula
Posts: 7,110
use an angle finder do a google search of measuring caster on a wrangler. it is simple.
jadmt is offline   Quote Quick Reply
Old 09-26-2013, 09:29 PM   #7
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
I was running TF lowers for a caster bump but decided to try the brackets. The flatten the angles and really make the jeep drive better.

I'm running stock CA's now. Arms aren't needed for caster but people do run both. I would either run only uppers (fine tune caster) or both.

Caster is a angle and putting the jeep on a rack is the only way to accurately measure side to side.
BUT.... You can get a close estimate by measuring pinion angle and doing some simple math.
The JK Has 6 degrees of separation Between caster and pinion. Rotating the pinion down gives you caster. Up gives you pinion.
Measure the pinion flange. Stock is going to be 2 degrees positive (up from 0) stock caster is 4 degrees. Added together you get that 6 degrees I talked about.

Here's some examples
Pinion flange = 0
Caster = 6

Pinion +1
Caster = 5

Pinion +3
Caster = 3

Pinion +2
Caster 4

Not going to be dead accurate but a close average between both sides.
kjeeper10 is online now   Quote Quick Reply
Old 09-26-2013, 09:31 PM   #8
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Editing on the app screws up the post.

My comment "arms aren't needed for caster" I mean along with the brackets. Just wanted to make that clear.
kjeeper10 is online now   Quote Quick Reply
Old 09-26-2013, 09:33 PM   #9
Jeeper
 
Join Date: Aug 2013
Posts: 116
Looking at that gives me a headache! Should of paid better attention in college math class.
Rightside is offline   Quote Quick Reply
Old 09-26-2013, 09:37 PM   #10
Jeeper
 
Join Date: Mar 2012
Posts: 49
OK, Brackets for me, then I will take it back to alignment shop to check.
Firefighter-rn is offline   Quote Quick Reply
Old 09-26-2013, 09:48 PM   #11
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Quote:
Originally Posted by Rightside View Post
Looking at that gives me a headache! Should of paid better attention in college math class.

Lol it's not that hard to understand.

6 degrees. Remember this number.

The front differential/pinion/pumpkin points up 2* stock. If you were to out a angle on the flange where the u-joint bolts to. It would read 2* or 88* (same)
Stock caster is 4* (or close to it)
There's that 6 degrees 4 + 2

Pinion and caster are adversely related. Changing your pinion angle changes caster angle
Now look at the examples again. Every example equals 6

I would post a link but you think this is confusing lol.
kjeeper10 is online now   Quote Quick Reply
Old 09-27-2013, 06:30 AM   #12
Jeeper
 
4DoorCrush's Avatar
 
Join Date: May 2012
Posts: 2,604
So what can I do to make my 2012 to drive better? I have a rancho 2 in sport lift and 35s.
__________________
2012 Crush Jk sport
4DoorCrush is online now   Quote Quick Reply
Old 09-27-2013, 08:04 AM   #13
Jeeper
 
Join Date: Mar 2012
Posts: 252
Quote:
Originally Posted by 4DoorCrush View Post
So what can I do to make my 2012 to drive better? I have a rancho 2 in sport lift and 35s.
Assuming your jeep has bump steer and wants to track into any low spot in the road. Feels like you need 2 hands to hold the steering wheel and when you hit the brakes it sometimes pulls.


1. Tire pressure 28-30psi
2. AEV geometry correction brackets. (they have holes for 2.5" lift)
3. Teraflex monster front track bar. (center your front axle and get rid of the flex in the stock track bar)

These 3 things and your jeep will be a pleasure to drive again.
About $350 and a little work.
guppy is offline   Quote Quick Reply
Old 09-27-2013, 09:01 AM   #14
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Quote:
Originally Posted by guppy View Post
Assuming your jeep has bump steer and wants to track into any low spot in the road. Feels like you need 2 hands to hold the steering wheel and when you hit the brakes it sometimes pulls. 1. Tire pressure 28-30psi 2. AEV geometry correction brackets. (they have holes for 2.5" lift) 3. Teraflex monster front track bar. (center your front axle and get rid of the flex in the stock track bar) These 3 things and your jeep will be a pleasure to drive again. About $350 and a little work.
I don't know here. At 2" lift drivability shouldn't change much. And bumpsteer is only caused by geometry changes/angles of the steering.

What tires and psi ?

Adjustable shocks setting ?
kjeeper10 is online now   Quote Quick Reply
Old 09-27-2013, 10:01 AM   #15
Jeeper
 
4DoorCrush's Avatar
 
Join Date: May 2012
Posts: 2,604
Quote:
Originally Posted by kjeeper10 View Post

I don't know here. At 2" lift drivability shouldn't change much. And bumpsteer is only caused by geometry changes/angles of the steering.

What tires and psi ?

Adjustable shocks setting ?
Its not bad handling like DW or anything.

Cooper discoverer s/t 35/12.5/17 at 40 psi. I've tried from 28-35 and it seems to be worse since they are D rated.

Fronts at 5 and rears at 3.

Think a better steering stabilizer would help
__________________
2012 Crush Jk sport
4DoorCrush is online now   Quote Quick Reply
Old 09-27-2013, 10:19 AM   #16
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Quote:
Originally Posted by 4DoorCrush View Post
Its not bad handling like DW or anything. Cooper discoverer s/t 35/12.5/17 at 40 psi. I've tried from 28-35 and it seems to be worse since they are D rated. Fronts at 5 and rears at 3. Think a better steering stabilizer would help
Woah...., nelly. 40 is way to much for a 35. I run 25 in my E rated 35's
kjeeper10 is online now   Quote Quick Reply
Old 09-27-2013, 10:53 AM   #17
Jeeper
 
4DoorCrush's Avatar
 
Join Date: May 2012
Posts: 2,604
Quote:
Originally Posted by kjeeper10 View Post

Woah...., nelly. 40 is way to much for a 35. I run 25 in my E rated 35's
I know bit going lower makes it worse
__________________
2012 Crush Jk sport
4DoorCrush is online now   Quote Quick Reply
Old 09-27-2013, 11:03 AM   #18
Jeeper
 
gorillahydrographics's Avatar
 
Join Date: Apr 2013
Location: Tucson, Az
Posts: 1,242
Quote:
Originally Posted by Firefighter-rn View Post
I was thinking of the Rancho Brackets, but do you think I would need Control Arms?
Kjeeper10 what CA are you running - Stock?

If you have the budget for adjustable CA...do that skip the brackets.
__________________
2013 Billet Silver 2 Door Sport -TeraFlex Elite Long Arm with Rock Krawler 3.5" Triple Rate Coils- Yukon 5.13 Gears - Detroit Locker (front)Eaton "E" Locker(rear) - TeraFlex Flip Kit/high Steer - Currie HD Tie Rod - Smittybilt XRC Front MoD Bumper w/stinger and Crawler Conceptz Skinny Rear Bumper - XRC 9000LB winch - XRC Flat Fenders - Cooper Discovery MT 35x12.50x17 - Custom Urban Camo Grill -
gorillahydrographics is offline   Quote Quick Reply
Old 09-27-2013, 11:06 AM   #19
Jeeper
 
gorillahydrographics's Avatar
 
Join Date: Apr 2013
Location: Tucson, Az
Posts: 1,242
Quote:
Originally Posted by 4DoorCrush View Post
So what can I do to make my 2012 to drive better? I have a rancho 2 in sport lift and 35s.

Thats to vauge to even begin to give you suggestions that are meaningful.
__________________
2013 Billet Silver 2 Door Sport -TeraFlex Elite Long Arm with Rock Krawler 3.5" Triple Rate Coils- Yukon 5.13 Gears - Detroit Locker (front)Eaton "E" Locker(rear) - TeraFlex Flip Kit/high Steer - Currie HD Tie Rod - Smittybilt XRC Front MoD Bumper w/stinger and Crawler Conceptz Skinny Rear Bumper - XRC 9000LB winch - XRC Flat Fenders - Cooper Discovery MT 35x12.50x17 - Custom Urban Camo Grill -
gorillahydrographics is offline   Quote Quick Reply
Old 09-27-2013, 11:25 AM   #20
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Quote:
Originally Posted by 4DoorCrush View Post
I know bit going lower makes it worse
This does not make sense. 40 is higher then what's put in the factory 32 (37 psi)

Have you tried mid 20's ?
kjeeper10 is online now   Quote Quick Reply
Old 11-12-2013, 10:44 AM   #21
Jeeper
 
Join Date: Jun 2013
Posts: 200
Not to hijack OP's thread but same topic...Can the geo brackets be added after a lift? Like I am doing a RK 2.5'' lift with front TB and Rancho 9000's. Will be running 315's. It was told to me that the Geo brackets wont be needed. Need is an opinion I guess. Want is another topic. Do I need geo brackets or do a just want them to improve ride quality? Or do I install the lift and get her aligned, drive it and see how it goes? I just dont want to waste time or $ with alignments multiple times. Thanks for your advice.
jj77 is offline   Quote Quick Reply
Old 11-12-2013, 10:46 AM   #22
MallCrawler

WF Supporting Member
::WF Moderator::
 
kjeeper10's Avatar
 
Join Date: Feb 2011
Location: Connecticut
Posts: 37,368
Quote:
Originally Posted by jj77 View Post
Not to hijack OP's thread but same topic...Can the geo brackets be added after a lift? Like I am doing a RK 2.5'' lift with front TB and Rancho 9000's. Will be running 315's. It was told to me that the Geo brackets wont be needed. Need is an opinion I guess. Want is another topic. Do I need geo brackets or do a just want them to improve ride quality? Or do I install the lift and get her aligned, drive it and see how it goes? I just dont want to waste time or $ with alignments multiple times. Thanks for your advice.
Yes you can. Are you going to run control arms ?

kjeeper10 is online now   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum 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 email address for yourself.
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

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 12:03 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC