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Issues with installing rear control arms and setting pinion angle

Napalmsundae

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Jul 7, 2019
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4
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Florida
I am installing the rubicon express 3.5" lift with monotube shocks on my 1999 Sahara. I'm having issues installing the rear control arms and setting the Pinion angle. It looks as though the arms ar too short and the spring mounts are at an odd angle.
104091
The installation procedures are a little confusing when it comes to setting the innicial lower control arm length.
104092

It says set the innicial length at 32 5/8", and goes on to state that the measurement should be 42.6". I have it set at 32 5/8 now. And it looks way too short. We are going to see how far we can extend these arms, but in the directions it does say final length should be '32 5/8 - 33.25 depending on lift'
 

Chris

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Salem, Oregon
It looks like all you have to do is slightly tilt the axle back and the top arms should bolt right in. The angle doesn’t matter as those joints have a lot of movement in them.

Don’t pay attention to the numbers, they are irrelevant. What matters is the bottom control arms are adjusted to the point where your upper joined bumper is perfectly center with the spring perch below it.

The uppers will then be used to dial in pinion angle. Any numbers they give you in the instructions for measurements of control arm lengths should only be used as rough estimates as there is no way they can be 100% accurate.
 

bobthetj03

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What Chis said. Jack the axle to full bump and adjust lowers so the jounce bumper sits as close to center of lower spring perch as you can, then use the uppers to set pinion angle.
 
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Napalmsundae

Napalmsundae

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Joined
Jul 7, 2019
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Location
Florida
Okay so we lined up the
It looks like all you have to do is slightly tilt the axle back and the top arms should bolt right in. The angle doesn’t matter as those joints have a lot of movement in them.

Don’t pay attention to the numbers, they are irrelevant. What matters is the bottom control arms are adjusted to the point where your upper joined bumper is perfectly center with the spring perch below it.

The uppers will then be used to dial in pinion angle. Any numbers they give you in the instructions for measurements of control arm lengths should only be used as rough estimates as there is no way they can be 100% accurate.
Did what you suggested. Lined bump stop up with lower spring perch. Looks wrong. Top is at an angle. Bottom is not.
20190802_172006.jpg
20190802_171955.jpg
 

Ante_Up

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Jun 3, 2019
Messages
77
Location
Oklahoma
Unfortunately that's how it goes... Mine turned out the same. You can buy angled spring perch correctors, or cut and relocate the top spring mounts
 

Chris

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Sep 28, 2015
Messages
40,545
Location
Salem, Oregon
Unfortunately that's how it goes... Mine turned out the same. You can buy angled spring perch correctors, or cut and relocate the top spring mounts
X2 to this. That's 100% normal. If you want to correct that, you need to remove the spring perches and relocate them (which involves cutting and welding).