Why only change upper control arms, or vice versa??
07-22-2009, 08:24 PM
#13
JK Enthusiast
Join Date: Mar 2009
Location: Cartagena
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
one more thing
if im plannig on buying the upper adjustable control arms because im buying new driveshafts, hsoul i need to buy the lower too???? becuase in the premium lift the lower control arms are not adjustable. or just with the upper ill be fine to adjust the axel???
thanks
if im plannig on buying the upper adjustable control arms because im buying new driveshafts, hsoul i need to buy the lower too???? becuase in the premium lift the lower control arms are not adjustable. or just with the upper ill be fine to adjust the axel???
thanks
07-22-2009, 08:53 PM
#14
JK Enthusiast
Join Date: Mar 2009
Location: Cartagena
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
and to adjust that i need to?????? because in the jk project install instructions it says the measurres but when you have both lower and upper control arms, how should i finely adjust the uppers when having the fixed lowers???
thanks for the info men
thanks for the info men
No. You can run upper adjustables with your fixed lowers to adjust your rear pinion angle and your front caster & pinion angle. You won't be able to fine tune everything as much, but you should be fine with your fixed lowers.
The Rubicon Express 3.5" Superflex kit actually comes that way--fixed lowers and adjustable uppers.
The Rubicon Express 3.5" Superflex kit actually comes that way--fixed lowers and adjustable uppers.
07-22-2009, 09:15 PM
#15
JK Enthusiast
Join Date: Jul 2008
Location: Rohnert Park, CA
Posts: 458
Likes: 0
Received 0 Likes
on
0 Posts
I just went ahead and replaced them all when I did mine (teraflex adjustables). I am running a 4" suspension lift on my 2dr with a 1 1"4 spacer in the back to keep the back level when loaded. Still running my stock driveshafts ( i have over 20k on them since the lift installed with no problems. knock on wood.) The reason I did them all though is because I could not pass up on the price. They were $800 new from 4wheelparts. They were having a clearance on them 
Last edited by FireRescue707; 07-22-2009 at 09:17 PM.
09-27-2009, 07:20 PM
#16
JK Freak
figured I'd bring this one back up as it has some great info..
My question, relating to the OP's question, is this.
Does anyone have any close measurements for the front uppers and rear lower arms on a Teraflex 3" lift? It'll be going on my JKU X. Soft top with auto trans. I plan to install my kit next friday. So, any close adjustments would be great. I'll only have a few days to install the kit and get it fine tuned as much as I can, heading back to my hometown for my bestfriends wedding.
-Chad-
My question, relating to the OP's question, is this.
Does anyone have any close measurements for the front uppers and rear lower arms on a Teraflex 3" lift? It'll be going on my JKU X. Soft top with auto trans. I plan to install my kit next friday. So, any close adjustments would be great. I'll only have a few days to install the kit and get it fine tuned as much as I can, heading back to my hometown for my bestfriends wedding.
-Chad-
09-29-2009, 05:12 AM
#17
JK Super Freak
Planman... does the adjustable control arms give you better flexibility... if so would it be better to go with the lower ones. Another food for thought... if you can replace either upper or lower, would it be better to replace the lowers since the after market ones seem to be stronger and the lower control arms are more exposed to getting damaged?
10-08-2009, 09:23 PM
#18
JK Newbie
Join Date: Aug 2009
Location: Wichita Falls, Tx
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
This is a great thread for a guy moving into a JK. Great.
And as I was reading that last post, Planman, I was popping knuckles and easing onto the edge of my seat getting ready to type this:
"The aftermarket arms are typically stronger than the stock control arm brackets.
I'd bet that if you hit something so hard or bound up your suspension so much that you would bend a stock arm, you would risk bending the stock brackets or even break the stock bracket welds on the front axle if you did the same thing with an aftermarket arm without adding additional welds and skids or gussets to the stock brackets."
Excellent thread... I definitely learned some critical things with the four door / auto /drive shaft conundrum..
And as I was reading that last post, Planman, I was popping knuckles and easing onto the edge of my seat getting ready to type this:
"The aftermarket arms are typically stronger than the stock control arm brackets.
I'd bet that if you hit something so hard or bound up your suspension so much that you would bend a stock arm, you would risk bending the stock brackets or even break the stock bracket welds on the front axle if you did the same thing with an aftermarket arm without adding additional welds and skids or gussets to the stock brackets."
Excellent thread... I definitely learned some critical things with the four door / auto /drive shaft conundrum..
10-09-2009, 07:31 AM
#20
JK Enthusiast
Join Date: Mar 2009
Location: In the Goldfeilds
Posts: 425
Likes: 0
Received 0 Likes
on
0 Posts
The upper rear arms are used to adjust the pinion angle of the rear axle when you add an aftermarket driveshaft:
The lower rear arms are used to lengthen your wheel base that is lost when you lift your rig. See how the rear wheels on this rig are more forward than stock because it was lifted 4" without rear lower control arms:
The front lower arms are used to either regain lost wheel base from a lift or to adjust the angle of the front axle for correct caster alignment, or both.
The front upper arms are used to adjust the angle of the front axle for correct caster alignment specs if the front lower arms were used to regain wheel base.
In some circumstances--like with the Currie adjustable front upper arms--front arms can be adjusted much shorter than stock for correct caster alignment specs if the stock arms are still used.
Caster shown in lower left corner:
So:
At 2.5" to 3", you can go with either adjustable front uppers or lowers to inprove your caster specs.
At 3" on a 2 door, you may eventually need to run an aftermarket driveshaft along with adjustable rear uppers.
In either case, at 2.5"-3" there is no need for all 8 adjustable arms, and the money could be better spent on other upgrades.
The lower rear arms are used to lengthen your wheel base that is lost when you lift your rig. See how the rear wheels on this rig are more forward than stock because it was lifted 4" without rear lower control arms:
The front lower arms are used to either regain lost wheel base from a lift or to adjust the angle of the front axle for correct caster alignment, or both.
The front upper arms are used to adjust the angle of the front axle for correct caster alignment specs if the front lower arms were used to regain wheel base.
In some circumstances--like with the Currie adjustable front upper arms--front arms can be adjusted much shorter than stock for correct caster alignment specs if the stock arms are still used.
Caster shown in lower left corner:
So:
- There is no need for rear upper adjustables unless you run an aftermarket driveshaft.
- There is no need for rear lower adjustables unless you feel a need to lengthen/regain your lost wheelbase caused by your lift.
- If you run Currie adjustable front uppers to adjust your caster specs, there is no need for adjustable lowers unless you want to fine tune your alignment or lengthen your wheelbase.
- There is no need for adjustable front uppers if you can properly correct your caster alignment specs with adjustable lowers.
At 2.5" to 3", you can go with either adjustable front uppers or lowers to inprove your caster specs.
At 3" on a 2 door, you may eventually need to run an aftermarket driveshaft along with adjustable rear uppers.
In either case, at 2.5"-3" there is no need for all 8 adjustable arms, and the money could be better spent on other upgrades.
Thanks again Planman - you always have some of the best info on here.