Centering Axle + Control Arm & Track Bar Lengths - JeepForum.com
 1Likes
  • 1 Post By DoodlesTJ
 
LinkBack Thread Tools
post #1 of 10 Old 09-27-2020, 08:34 AM Thread Starter
DoodlesTJ
Registered User
2006 TJ Wrangler 
 
Join Date: Aug 2016
Posts: 100
Garage
Centering Axle + Control Arm & Track Bar Lengths

Hey guys so I just bought the Savvy 3Ē adjustable lift with fully adjustable control arms and track bars as well as the Savvy tummy tuck under armor.

While Iím installing this I want to make sure I have the correct ideas about how to get all my control arm + track bar lengths set up properly as well as the axle centered.

Hereís what Iím thinking:

Centering the axle:

With the Jeep on level ground and everything installed, disconnect the front and rear track bars. Bounce up and down on both front and rear bumpers to allow the axles to self-center. Check this by placing a 4í level vertically against the outside of the tires and measuring from there to a point inside the fender well, making sure that this is the same for both passenger and driver side.
When it is the same, adjust the track bars so they fit in the mount and bolt them up. Voila, axles centered.

Lower control arms front and rear:

With everything connected simply adjust these to position the tires within the wheel wells. Kind of a matter of preference from what Iíve been reading. Just make sure there isnít unnecessary rubbing on the front when at full turn. Iíll probably try to center all wheels front to back in their wheel wells. Do a final check to make sure that the distance between front and rear axle hubs on both driverís and passengerís sides are the same.

Front upper control arms:

Adjusting these sets the caster. I probably want about 7* of it. Place an angle finder on the top of the axle C (where the ball joint is) and rotate the UCAs until it reads 7*. This means that the upper part of the C should be pointed slightly more towards the rear of the vehicle than the lower part of the C does.

Rear upper control arms:

Since I have the NP241 and double cardan driveshafts I will just adjust the UCAs until the driveshaft makes a straight line with the rear differentialís pinion. Use an angle finder to check for accuracy. I have the rear track bar relocation bracket and rear shock outboarding brackets to make this rotation of the axle feasible.

^Does all of this sound correct? Did I miss anything?

Thanks guys! Iíll make a video of all of this once I have a good understanding and actually do it.


-'06 TJ converted to a Rubicon
DoodlesTJ is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 09-27-2020, 11:46 AM
Mousejockey
Registered User
2002 TJ Wrangler 
 
Join Date: Jun 2010
Location: Rio Linda
Posts: 1,428
Track bar adj, Yes
Control arms are a bit more involved. The rear axle should be squared with the centerline of the vehicle - Thrust Line
Upper and lower arms are adjusted so that the axle is centered, squared and proper caster in the front and pinion angle in the rear.
Alot of guys will remove the front springs so that they can move the axle up, down and all positions possible to check for binding, clearance, and bump stop alignment
Mousejockey is offline  
post #3 of 10 Old 09-28-2020, 04:12 PM Thread Starter
DoodlesTJ
Registered User
2006 TJ Wrangler 
 
Join Date: Aug 2016
Posts: 100
Garage
Okay so basically the rear and front lower control arms should be the exact same length to keep the axle square?

Hmmm I hadn't thought of that last part. I guess I could remove the springs. I also feel like you could check that stuff with them still in place though

-'06 TJ converted to a Rubicon
DoodlesTJ is offline  
 
post #4 of 10 Old 09-30-2020, 08:33 PM
chrisman2552
Registered User
 
chrisman2552's Avatar
2003 TJ Wrangler 
 
Join Date: Jun 2017
Location: Halifax
Posts: 14
Garage
Reason to remove the springs is to help you get proper alignment of the bump stops on the axle. Its just also a lot easier to move the axle upwards into the wheel well if you're not fighting springs.
chrisman2552 is offline  
post #5 of 10 Old 10-01-2020, 12:13 AM
Mousejockey
Registered User
2002 TJ Wrangler 
 
Join Date: Jun 2010
Location: Rio Linda
Posts: 1,428
Quote:
Originally Posted by DoodlesTJ View Post
Okay so basically the rear and front lower control arms should be the exact same length to keep the axle square?

No
That would be true if the mounts on the frame and on the axle were square with each other and the frame was true.
But ours is not a perfect world, it will get ya close however
Measuring using the holes in the frame to axle bolts will get ya close also.

More important is to not 'twist' the axle by having one or opposing arms too short or long
Mousejockey is offline  
post #6 of 10 Old 10-01-2020, 07:05 AM
rikkards
Web Wheeler
 
rikkards's Avatar
1998 TJ Wrangler 
 
Join Date: Jun 2008
Location: Ottawa
Posts: 4,630
Quote:
Originally Posted by Mousejockey View Post
No
That would be true if the mounts on the frame and on the axle were square with each other and the frame was true.
But ours is not a perfect world, it will get ya close however
Measuring using the holes in the frame to axle bolts will get ya close also.

More important is to not 'twist' the axle by having one or opposing arms too short or long

This, I usually measure both sides from middle TC Skid hole to opposite side axle like a bracket. That should get your rear square which you can then use to get the front square from that

Machete don't tweet
- Machete
rikkards is offline  
post #7 of 10 Old 10-01-2020, 10:24 AM Thread Starter
DoodlesTJ
Registered User
2006 TJ Wrangler 
 
Join Date: Aug 2016
Posts: 100
Garage
Thanks guys, I'll try that method in the next few days. I was just trying to go from front hub to the rear hubs to make sure that was even (front currently has stock CAs, rear has the adjustable CAs installed).

-'06 TJ converted to a Rubicon
DoodlesTJ is offline  
post #8 of 10 Old 10-02-2020, 12:46 PM Thread Starter
DoodlesTJ
Registered User
2006 TJ Wrangler 
 
Join Date: Aug 2016
Posts: 100
Garage
I ended up using the bracket for the middle body mount bolt and measured from there to the center of the lower control arm bracket. Each side was exactly the same so I figure it's good.

Also previously got my axle centered using a ratchet strap. Adjusted lower control arms to position the wheels in the wheel well like I said then the upper until the pinion angle was 1 degree less than the driveshaft angle. Now everything in the rear should be good, just have to do the same in the front and set caster

-'06 TJ converted to a Rubicon
DoodlesTJ is offline  
post #9 of 10 Old 10-02-2020, 02:16 PM
NashvilleTJ
I miss the snow...
 
NashvilleTJ's Avatar
2004 LJ Wrangler 
 
Join Date: Jul 2010
Location: Nashville
Posts: 4,381
Dirt Lifestyle did a great video on doing a 4 wheel alignment. May be worth a look:


Build Thread:

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Swing Away / Swing Down Tire Carrier:

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
NashvilleTJ is offline  
post #10 of 10 Old 10-07-2020, 07:40 AM Thread Starter
DoodlesTJ
Registered User
2006 TJ Wrangler 
 
Join Date: Aug 2016
Posts: 100
Garage
Thank you that video was perfect! Will get on that soon, need to buy some laser levels
NashvilleTJ likes this.

-'06 TJ converted to a Rubicon
DoodlesTJ is offline  
Reply

Tags
lift , savvy

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.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome