Question about Adjustable control arms - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 05-26-2007, 03:38 PM   #1
Jeeper
 
jherrin215's Avatar
 
Join Date: Dec 2006
Location: Glasgow, KY
Posts: 1,002
Question about Adjustable control arms

I understand the concept of adjustable control arms, and why you need them, but my question is how do you adjust them?? Is there a certain measurement that you have to take when adjusting them to get them the right length or what?? How do you know how long to make them when adjusting is more of what I am trying to ask. Thanks

__________________

2003 Light Khaki Sahara
jherrin215 is offline   Quote Quick Reply
Old 05-27-2007, 02:44 AM   #2
Jack Lives Here!!!

WF Supporting Member
 
1BLKJP's Avatar
 
Join Date: Apr 2005
Location: Phoenix, AZ
Posts: 7,764
If you mess around with this stuff long enough then you just start to get the feel of what looks right. When you are sdjusting your rear pinion angle you want it 1 to 2 degree's beneath the rear output shaft of your TCase. In the front you want the appropriate amount of caster to make your suspension and your front dshaft happy.

Arms can be adustable in a couple ways. If they have right and left hand thread then you can adjust them in the vehicle. If not then you have to remove one or both ends and adjust them that way. Rule of thumb is just to adjust both sides the same length.

__________________
Thanks,
Jack Hickman

President - Arizona Off-Highway Vehicle Coalition
Vice-President - ASA4WDC
Arizona Rock Rats
1BLKJP is offline   Quote Quick Reply
Old 05-27-2007, 10:33 AM   #3
WINNAR!!!!!!
 
MR.CLIFFORD's Avatar
 
Join Date: Nov 2005
Location: THE PROVING GROUNDS
Posts: 6,591
While I agree that the visuals will usually get you there I believe that it is hard to get your vehicles thrust angle correct. This is usually only a factor if you are replacing all 8 control arms. You can get it close but a digital computer alignment is usually the only way you will find out how true you are.
MR.CLIFFORD is offline   Quote Quick Reply
Old 05-27-2007, 11:20 AM   #4
Jeeper
 
jherrin215's Avatar
 
Join Date: Dec 2006
Location: Glasgow, KY
Posts: 1,002
So if I get a set of adjustable control arms what would I need to do? Take it somewhere and have them installed and adjusted, or install them myself and have them adjusted, or install them myself and try to figure out how to get them adjusted out right??
__________________

2003 Light Khaki Sahara
jherrin215 is offline   Quote Quick Reply
Old 05-27-2007, 11:25 AM   #5
coilovers are damn flexy
 
bluvikng's Avatar
 
Join Date: Mar 2006
Location: Texas
Posts: 3,260
Are you replacing all 8 CA's, or just the four uppers?
bluvikng is offline   Quote Quick Reply
Old 05-27-2007, 11:54 AM   #6
Member
 
Join Date: May 2007
Posts: 27
Quote:
Originally Posted by 1BLKJP View Post
If you mess around with this stuff long enough then you just start to get the feel of what looks right. When you are adjusting your rear pinion angle you want it 1 to 2 degree's beneath the rear output shaft of your TCase.
I see that tossed about a lot as the rule and I often wonder why? Personally I'd never do it that way, but there is some reason for it, eh?

Quote:
Rule of thumb is just to adjust both sides the same length.
Typically, the lower mounts are much stronger and less likely to get moved around, the uppers on the other hand, are relatively easy to move around.

That said, I start with both lowers the same length, install them and roughly adjust the pinion angle with a floor jack.

Then center the axle. After the axle is centered, install 1 upper and fine tune the pinion angle.

The last upper gets floated between the bolt holes. If you jack the axle around and compress either of the joints in the arm trying to get the bolt lined up, it will wind up preloaded and stress the joint material.

Since cross caster isn't adjustable with the control arms, it doesn't make sense to try and do it.
mrblaine is offline   Quote Quick Reply
Old 05-27-2007, 11:52 PM   #7
Jeeper
 
jherrin215's Avatar
 
Join Date: Dec 2006
Location: Glasgow, KY
Posts: 1,002
Quote:
Originally Posted by mrblaine View Post
I see that tossed about a lot as the rule and I often wonder why? Personally I'd never do it that way, but there is some reason for it, eh?



Typically, the lower mounts are much stronger and less likely to get moved around, the uppers on the other hand, are relatively easy to move around.

That said, I start with both lowers the same length, install them and roughly adjust the pinion angle with a floor jack.

Then center the axle. After the axle is centered, install 1 upper and fine tune the pinion angle.

The last upper gets floated between the bolt holes. If you jack the axle around and compress either of the joints in the arm trying to get the bolt lined up, it will wind up preloaded and stress the joint material.

Since cross caster isn't adjustable with the control arms, it doesn't make sense to try and do it.
WOW!! I guess I need to get some one to do it for me cause that was way over my head!! I thought I had a pretty good grasp on things but that made me feel dumb reading that!!
__________________

2003 Light Khaki Sahara
jherrin215 is offline   Quote Quick Reply
Old 05-28-2007, 12:13 PM   #8
Member
 
Join Date: May 2007
Posts: 27
Quote:
Originally Posted by jherrin215 View Post
WOW!! I guess I need to get some one to do it for me cause that was way over my head!! I thought I had a pretty good grasp on things but that made me feel dumb reading that!!
Take it one step at a time. It's not hard.
mrblaine is offline   Quote Quick Reply
Old 05-28-2007, 03:19 PM   #9
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 33,154
Images: 2
Good thread that got me thinking. My TJ's thrust angle hasn't been checked since installing my last suspension so I will put that on my short list.

Blaine, can the thrust angle be measured accurately enough with just the careful use of a tape measure? I don't mean the actual angle but you know what I mean. It seems to drive fine but I just never gave much thought to the thrust angle due to having set the lower arms to the exact same lengths.
__________________
When you have a choice, buy American.

Jerry Bransford is online now   Quote Quick Reply
Old 05-28-2007, 04:21 PM   #10
Member
 
Join Date: May 2007
Posts: 27
Quote:
Originally Posted by Jerry Bransford View Post
Good thread that got me thinking. My TJ's thrust angle hasn't been checked since installing my last suspension so I will put that on my short list.

Blaine, can the thrust angle be measured accurately enough with just the careful use of a tape measure? I don't mean the actual angle but you know what I mean. It seems to drive fine but I just never gave much thought to the thrust angle due to having set the lower arms to the exact same lengths.
Get someone to hold the end of a tape against the inside of your rear axle tube out near the tire. You read the dimensions at the front axle tube. Make sure your rig is on level ground and you don't have it loaded funny from side to side.

As you tilt the rig, the axles will move away from each other on one side and towards each other on the other making it hard to get an accurate reading.

If it's close and it's not handling funny, then it's likely close enough.
mrblaine is offline   Quote Quick Reply
Old 05-28-2007, 04:33 PM   #11
WINNAR!!!!!!
 
MR.CLIFFORD's Avatar
 
Join Date: Nov 2005
Location: THE PROVING GROUNDS
Posts: 6,591
I usually set my tape inside the axle tubes and lock the tape down. Have someone hold the dumb end of the tape equal distance in from the outer flange and butt the tape to the front axle tube. You can get a pretty good reading using that method. If your measurement is out of whack though how do you know which axle is not square to the frame(which isn't the best analogy).

A free computer alignment check up will tell you exactly how much each axle is out and better help you determine where to go.

MR.CLIFFORD is offline   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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Adjustable front lower control arms kg4kpg Classifieds Archive 0 09-21-2007 11:05 PM
Adjustable control arms? gregg bowie TJ Tech Forum 4 06-20-2006 11:44 PM
lower adjustable control arms mrbigjeep TJ Tech Forum 3 05-23-2006 12:44 PM
adjustable control arms? mrbigjeep TJ Tech Forum 2 05-03-2006 02:14 AM
Adjustable control arms, reinforced diff covers dwcustoms Classifieds Archive 0 12-30-2005 11:23 AM



Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 02:24 PM.



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