HOW TO: Properly Adjust 8 Adjustible Contol Arms

DWiggles

Caught the Bug
I have noticed on a few of the threads around the forum that people are setting up there adjustable control arms based on various manufacture control arm length recommendations. While this is a great place to start, it is not the end all, be all, prefect setup for every jeep. Due to Manufacturing tolerance and the nature of mass producing a product, each jeep is going to need a tweak here or there from the printed control arm manufacturer suggested lengths. Regardless of what Brand control arms you have on your jeep, or what lift, this write up is about properly setting up your adjustable control arms for your specific jeep. You paid for adjustable arms, so here is how to utilize that adjustablilty:

What You Will Need:

- Jack

-Jack Stands

-Angle Finder

-Measuring Tape

-Writing Utensils

-18mm & 21mm Sockets and Wrenches

-Torque Wrench

-Whatever else you need to adjust your control arms



BEFORE YOU GET STARTED:

Be sure your control arms are already set to your specific Manufacturer’s suggested lengths and you already have the proper bump stops for your setup. Make sure your Jeep is in Park (in gear for manual) and the parking brake is set!!


What You Will Need to Know:

FRONT UPPER Control arms are used to SET PINION/CASTER angle ONLY

REAR LOWER Control arms are used to SET PINION angle ONLY

FRONT LOWER Control arms are used to MOVE THE AXLE

REAR UPPER Control arms are used to MOVE THE AXLE

What You Will Need To Do Per Axle:

1. Place a floor jack under the axle and raise it up until the front wheels are off the ground. Set your frame AND axle back down onto jack stands for safety and then use a 19mm socket to remove the lug nuts on your wheels.

2.Remove the wheels and set them aside.

3. Remove your front springs, set them aside (some setups will require removing the bump stop extensions with the spring, simply bolt your bump stop extensions back in place once the springs have been removed) **If you need to adjust your bump stops, now is the time to do it!

4.Using an 18mm and 21mm wrenches and sockets, loosen, but do not remove both upper and lower control arm axle mount bolts

5.Place a floor jack under the center of your front axle and jack it up until the axle is at full bump.

6.Remove both upper control arm axle mount bolts.

7.Lengthen or shorten your lower control arms (left and right) until your bump stops are centered with the factory jounce tubes on both sides. **NOTE: while you adjust the driver side control arm, the passenger side will move so be sure to go back and check both sides before moving on

8. Once both driver and passenger side bumps are centered, lengthen/shorten BOTH upper control arms until you can loosely bolt them back on. Don’t worry about your pinion angle just yet.

9.Reinstall your springs & wheels.

10.Slowly and carefully lower your jeep until the suspension is fully weighted. Take a minute to double check by taking a step back to visually insure both wheels are in the same position according to the wheel wells.

Note: they will most likely NOT be centered in the wheel well. But they should be the same left to right.

if something is off, it is MUCH easier to go back and fix now.

11.Place a floor jack under the front diff and take some tension off the uppers control arms and place jack stands under the frame just in case your jack slips or axle rotates.

12.Remove both upper control arms axle mount bolts.

13. Using an angle finder, check your caster/pinion angle on your front axle. Adjust using your floor jack on the pinion.

14.Once you have the pinion/caster angle the way you want it, lengthen/shorten the driver side upper control arm until the bolt slides easily into the axle mount, loosely bolt it on.

15. Remove your jack from the pinion, the jeep should now be resting at ride height will 3 of the 4 arms connected to the axle. Now adjust the passenger side upper control arm until the bolt slides easily into the mount. Loosely Bolt it on.

16. To verify that the axle is actually perpendicular to the frame, measure the distance from the axle tube to the first body mount on both the driver and passenger side. Write down the measurements you just took! **As a “Measure twice, cut once” fail safe, also measure from the same place on the axle to the second body mount or any other parallel constant. Again, both driver and passenger side. Again, WRITE IT DOWN! If your measurements came out square, you can skip the next step.

17. Now keeping in mind that there will be tolerance involved with mass production vehicles, we are only really interested in splitting the difference in the measurements. I.E. Say the difference on the first measurement (to body mount) says the Passenger Side needs to come back ½” but the second measurement (to cross memeber) says the Passenger Side is ¼” to far forward, split the difference, and move the passenger side axle back by shortening the lower Passenger Side control arm 1/8”. **Remember to MOVE the axle, we need to remove the bolts from BOTH upper control arms BEFORE adjusting the lower control arm. Then repeat steps 13-17 until you are happy with the results.

18. Torque all control arm mounting bolts/jam nuts/lock bolts etc. to their respective torque specs.

19.Repeat this process on the other axle.

If you have anything to add or know a better way to do this, feel free to post it up! This is just the way I did it in my driveway on my jeep after installing my long arms. :thumb: *
 
Last edited:

aTX427

New member
Wouldn't you want to adjust and bolt up the second upper control arm when you get the pinion where you want before taking the pinion off the jack? Also, are there any centered bolts that would allow you to triangulate the axle to frame that you can then use to square up the rear to the front??
 

DWiggles

Caught the Bug
Edited the original post for formatting.

Atx427, yes. You will want A bolt through 1 control arm and it's respective axle mount before lowering the jack from holding up the pinion, but you don't want to torque it until it is loaded with the weight of the vehicle. This thread is mainly a catch all, if you are running a Johnny joint, you can obviously torque it down at any time. But if you are using something with static, rubber bushings, you need to torque the axle when it is at ride height otherwise you will introduce rotational load into the joint causing premature failure of said joint.

If you can find a bolt to triangulate from, more power to you. But that MAY be specific to chassis, rig from, and factory equipment. So keep that in mind. What works for a automatic 2wd 2 door sport, may not work for a manual 4 door Rubicon and so on. The method suggested above will work on ANY solid axle vehicle. Not just jeeps.

sent from SPACE!
DZZ Build thread
 
Last edited:

newbie731

New member
Good read

I am so hyping myself up to take a day and do this from start to finish just to see what the before and after looks like
 

newbie731

New member
Step 1. ???

Am I reading correctly that I should put a set of jack stands under the frame as well as a set of jack stands under the front axle? Seems it would be difficult to remove springs with stands under the axle as I wouldn't be able to create the suspension droop required to assist in spring removal.

I was thinking stands under the frame and use floor jack to manipulate the required suspension travel.

. . . Lol or did I totally just over think that?
 

wjtstudios

Hooked
Am I reading correctly that I should put a set of jack stands under the frame as well as a set of jack stands under the front axle? Seems it would be difficult to remove springs with stands under the axle as I wouldn't be able to create the suspension droop required to assist in spring removal.

I was thinking stands under the frame and use floor jack to manipulate the required suspension travel.

. . . Lol or did I totally just over think that?

That’s the way I’ve done it. Two stands under the frame and two floor jacks under the axles.


2015 JKUR AEV JK350
1985 CJ8 Scrambler
 

jesse3638

Hooked
Am I reading correctly that I should put a set of jack stands under the frame as well as a set of jack stands under the front axle? Seems it would be difficult to remove springs with stands under the axle as I wouldn't be able to create the suspension droop required to assist in spring removal.

I was thinking stands under the frame and use floor jack to manipulate the required suspension travel.

. . . Lol or did I totally just over think that?
Yep I just did that when I swapped my springs. Two 12 tons on the frame and a floor jack to lower the axle. Remember to unsecure or disconnect all the locker and wheel speed sensor wiring before lowering them. Don't want to damage them so just go slow when you bring it down.

Sent from my SM-G973U using WAYALIFE mobile app
 
Last edited:

woof359

Member
I have noticed on a few of the threads around the forum that people are setting up there adjustable control arms based on various manufacture control arm length recommendations. While this is a great place to start, it is not the end all, be all, prefect setup for every jeep. Due to Manufacturing tolerance and the nature of mass producing a product, each jeep is going to need a tweak here or there from the printed control arm manufacturer suggested lengths. Regardless of what Brand control arms you have on your jeep, or what lift, this write up is about properly setting up your adjustable control arms for your specific jeep. You paid for adjustable arms, so here is how to utilize that adjustablilty:

What You Will Need:

- Jack

-Jack Stands

-Angle Finder

-Measuring Tape

-Writing Utensils

-18mm & 21mm Sockets and Wrenches

-Torque Wrench

-Whatever else you need to adjust your control arms



BEFORE YOU GET STARTED:

Be sure your control arms are already set to your specific Manufacturer’s suggested lengths and you already have the proper bump stops for your setup. Make sure your Jeep is in Park (in gear for manual) and the parking brake is set!!


What You Will Need to Know:

FRONT UPPER Control arms
are used to SET PINION/CASTER angle ONLY

REAR LOWER Control arms
are used to SET PINION angle ONLY

FRONT LOWER Control arms
are used to MOVE THE AXLE

REAR UPPER Control arms
are used to MOVE THE AXLE

What You Will Need To Do Per Axle:


1. Place a floor jack under the axle and raise it up until the front wheels are off the ground. Set your frame AND axle back down onto jack stands for safety and then use a 19mm socket to remove the lug nuts on your wheels.

2.Remove the wheels and set them aside.

3. Remove your front springs, set them aside (some setups will require removing the bump stop extensions with the spring, simply bolt your bump stop extensions back in place once the springs have been removed) **If you need to adjust your bump stops, now is the time to do it!

4.Using an 18mm and 21mm wrenches and sockets, loosen, but do not remove both upper and lower control arm axle mount bolts

5.Place a floor jack under the center of your front axle and jack it up until the axle is at full bump.

6.Remove both upper control arm axle mount bolts.

7.Lengthen or shorten your lower control arms (left and right) until your bump stops are centered with the factory jounce tubes on both sides. **NOTE: while you adjust the driver side control arm, the passenger side will move so be sure to go back and check both sides before moving on

8. Once both driver and passenger side bumps are centered, lengthen/shorten BOTH upper control arms until you can loosely bolt them back on. Don’t worry about your pinion angle just yet.

9.Reinstall your springs & wheels.

10.Slowly and carefully lower your jeep until the suspension is fully weighted. Take a minute to double check by taking a step back to visually insure both wheels are in the same position according to the wheel wells.

Note: they will most likely NOT be centered in the wheel well. But they should be the same left to right.

if something is off, it is MUCH easier to go back and fix now.

11.Place a floor jack under the front diff and take some tension off the uppers control arms and place jack stands under the frame just in case your jack slips or axle rotates.

12.Remove both upper control arms axle mount bolts.

13. Using an angle finder, check your caster/pinion angle on your front axle. Adjust using your floor jack on the pinion.

14.Once you have the pinion/caster angle the way you want it, lengthen/shorten the driver side upper control arm until the bolt slides easily into the axle mount, loosely bolt it on.

15. Remove your jack from the pinion, the jeep should now be resting at ride height will 3 of the 4 arms connected to the axle. Now adjust the passenger side upper control arm until the bolt slides easily into the mount. Loosely Bolt it on.

16. To verify that the axle is actually perpendicular to the frame, measure the distance from the axle tube to the first body mount on both the driver and passenger side. Write down the measurements you just took! **As a “Measure twice, cut once” fail safe, also measure from the same place on the axle to the second body mount or any other parallel constant. Again, both driver and passenger side. Again, WRITE IT DOWN! If your measurements came out square, you can skip the next step.

17. Now keeping in mind that there will be tolerance involved with mass production vehicles, we are only really interested in splitting the difference in the measurements. I.E. Say the difference on the first measurement (to body mount) says the Passenger Side needs to come back ½” but the second measurement (to cross memeber) says the Passenger Side is ¼” to far forward, split the difference, and move the passenger side axle back by shortening the lower Passenger Side control arm 1/8”. **Remember to MOVE the axle, we need to remove the bolts from BOTH upper control arms BEFORE adjusting the lower control arm. Then repeat steps 13-17 until you are happy with the results.

18. Torque all control arm mounting bolts/jam nuts/lock bolts etc. to their respective torque specs.

19.Repeat this process on the other axle.

If you have anything to add or know a better way to do this, feel free to post it up! This is just the way I did it in my driveway on my jeep after installing my long arms. :thumb: *
question I have is when you add the rebuildible joints how much grease do you pump in the first time ?
 

wayoflife

Administrator
Staff member
question I have is when you add the rebuildible joints how much grease do you pump in the first time ?
Did they come dry or was there some grease in them already? Either way, should pump in as much as you start to see the seal start to bulge. You an almost feel it get to full capacity. If some grease comes out, it's not the end of the world. If there's grease in them already, it'll be a pump or two. If dry, it'll take quite a few pumps.

I should note this is easier to do BEFORE installing the arms on your Jeep.
 

woof359

Member
rough country lower arms, these, unlike the last set I got, were already assmebled. looked clean and dry
 

jcbfshr

New member
Note: they will most likely NOT be centered in the wheel well. But they should be the same left to right.

Reviving this thread as I am installing suspension and I’m just about to the point of dialing in control arm length/alignment.

I’m installing 3.5” Rockkrawler springs with correction pads in the rear. Fox coilovers in the front with air bumps aiming for 4.5” lift. Metalcloak control arms all around.

Regarding the statement above: when/how do I ensure that my axles are centered in the wheel well? Is it just a matter of add length to the control arms until they are centered? The rear is easy to measure for center, but what about the front? My bump stop mounts on the rear axle have some forward/back adjustment so that should give me adjustment as needed. Is there any guideline for upper limit of adjustment on my control arms (e.g. how much is the maximum thread that should be showing)? They are Metacloak mid arms.

Sorry for all the questions. When I first installed the control arms, I set them to the factory length plus half an inch and they were way off and my axle was way out of center and the springs were bowed a bunch.
 

WJCO

Meme King
Reviving this thread as I am installing suspension and I’m just about to the point of dialing in control arm length/alignment.

I’m installing 3.5” Rockkrawler springs with correction pads in the rear. Fox coilovers in the front with air bumps aiming for 4.5” lift. Metalcloak control arms all around.

Regarding the statement above: when/how do I ensure that my axles are centered in the wheel well? Is it just a matter of add length to the control arms until they are centered? The rear is easy to measure for center, but what about the front? My bump stop mounts on the rear axle have some forward/back adjustment so that should give me adjustment as needed. Is there any guideline for upper limit of adjustment on my control arms (e.g. how much is the maximum thread that should be showing)? They are Metacloak mid arms.

Sorry for all the questions. When I first installed the control arms, I set them to the factory length plus half an inch and they were way off and my axle was way out of center and the springs were bowed a bunch.
What's your question?
 

jcbfshr

New member
What's your question?

My biggest question is: how do I ensure my axle is centered in the wheel well? When I installed the control arms, I set them to factory length plus .5” and they were not even close. Most lift kits seem to indicate that to be the correct length (give or take a half an inch), which makes me question what I might be doing wrong.
 

wayoflife

Administrator
Staff member
My biggest question is: how do I ensure my axle is centered in the wheel well? When I installed the control arms, I set them to factory length plus .5” and they were not even close. Most lift kits seem to indicate that to be the correct length (give or take a half an inch), which makes me question what I might be doing wrong.
I would never pretend to know as much as what "most lift kits indicate" but 1/2" over factory is way too long. You need to remember that your axles travel in an arc and at 1/2", you axles will MISS the bumpstops or be at the very edge of them at a full bump AND will cause problems like your coils rubbing on things like your coils and track bars making contact with things like your differentials. AT MOST, the length you'd be adding to your lower control arms, to make your axles "look" more centered at ride height should only be about 1/4" at most or at least, for 3.5" of lift.
 

jcbfshr

New member
I would never pretend to know as much as what "most lift kits indicate" but 1/2" over factory is way too long. You need to remember that your axles travel in an arc and at 1/2", you axles will MISS the bumpstops or be at the very edge of them at a full bump AND will cause problems like your coils rubbing on things like your coils and track bars making contact with things like your differentials. AT MOST, the length you'd be adding to your lower control arms, to make your axles "look" more centered at ride height should only be about 1/4" at most or at least, for 3.5" of lift.

Thanks for the reply! Sounds like I have more measuring and cycling to do to really dial things in. I’ll likely start over from what my factory arms were and add incrementally from there until I get things set to a more realistic place.
 
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