Upper Control Arm Length

MHorschel32

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I have a JL Rubicon with the TeraFlex ST1 Spacer lift. It has a 2” spacer up front and I have just purchased the MetalCloak Adjustable control arms to get some Caster back. My current pinion angle measures at 5 degrees roughly and am looking to shorten the arms 1/4” to get me close to 6. I’m looking for a sanity check with the forum to see if this is inline with what others have done. I want the caster back due to the increased steering control but do not want to bind up my driveshaft as it is the stock.

 

Roky

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I have a JL Rubicon with the TeraFlex ST1 Spacer lift. It has a 2” spacer up front and I have just purchased the MetalCloak Adjustable control arms to get some Caster back. My current pinion angle measures at 5 degrees roughly and am looking to shorten the arms 1/4” to get me close to 6. I’m looking for a sanity check with the forum to see if this is inline with what others have done. I want the caster back due to the increased steering control but do not want to bind up my driveshaft as it is the stock.
Driveshaft will be fine.
 

Moregone

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Mopar lower control arms would be the cheapest way to put some more caster back into the front end.

Curious why you're opting for for adjustable uppers. Seems most people start with the lowers.

6 degrees is where I'm at upfront right now after 2.5" lift with longer non adjustable lower control arms. I still feel a little floaty and see a lot of people are going to 7 degrees to get the planted feeling on the road.

Someone correct me if I'm wrong but there is less urgency getting front drive shafts on the JL because of the FAD. When you're in 2wd the front shaft isn't spinning. If you drive a lot of miles in 4Wd then disregard. But even offroading I stay in 2WD a good bit.
 

word302

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I have a JL Rubicon with the TeraFlex ST1 Spacer lift. It has a 2” spacer up front and I have just purchased the MetalCloak Adjustable control arms to get some Caster back. My current pinion angle measures at 5 degrees roughly and am looking to shorten the arms 1/4” to get me close to 6. I’m looking for a sanity check with the forum to see if this is inline with what others have done. I want the caster back due to the increased steering control but do not want to bind up my driveshaft as it is the stock.
I'm assuming you mean caster angle and not opinion angle? If that's the case your drive shaft will be fine.
 

AnnDee4444

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I've seen lower control arms recommended more because their effect on wheelbase is less. Shortening the upper control arm 1/4" will shorten the wheelbase more than extending the lower control arm will lengthen the wheelbase. Basically the UCA mount is offset more from the axle's centerline than the LCA mount. Both are equally effective at changing caster (& pinion angle).

From what I've read, the front driveshaft becomes an issue when the front shocks exceed 28"-29". I would expect that the increased caster would make the situation slightly worse.

Also for anyone else with LCA drop brackets, the caster change under droop will be different than OEM, (probably worse if my logic is correct).
 


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MHorschel32

MHorschel32

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So I installed the UCA and shortened them 1/4” from stock with the spacer lift. Caster is now approximately 6 degrees and the steering is noticeably less floaty.

 

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