Mopar LCA swap

[Notams]

Lol. I just read through all 29 pages of this thread and now know more than I ever wanted to know about installing LCA's, measuring caster, and how reading a computer screen for an hour gives me a headache. Thanks to all of the posters for taking the time to pass your knowledge.

Just when I had everything figured out and was getting ready to head out to the garage and install my Teraflex Alpine adjustables (may lift more in the future), Page 26 threw me off. Hurricanes99 asked if it was necessary to crack the torque on the UCA's when installing longer LCA's. Mwilk012 answered yes, it's a good idea. But from reading everyone else's installs, I don't recall anyone else ever mentioning this. It sounds logical, but I wonder how necessary it is if your not extending the LCA's by much.

I swapped out my stock Sport S suspension for Rubicon Springs and Shocks with a .5 inch front spacer lift (to level out rake). I got about 1.5" lift out of it, so I intend to go with 24-1/4 as initial adjustment on the LCA's. I am currently sitting at 5.5* caster and it is a little twitchy at speed.

So with all of that said, will a slight increase in length of the LCA's require a break and re-torque on the UCA's?

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[Roky]

Lol. I just read through all 29 pages of this thread and now know more than I ever wanted to know about installing LCA's, measuring caster, and how reading a computer screen for an hour gives me a headache. Thanks to all of the posters for taking the time to pass your knowledge.

Just when I had everything figured out and was getting ready to head out to the garage and install my Teraflex Alpine adjustables (may lift more in the future), Page 26 threw me off. Hurricanes99 asked if it was necessary to crack the torque on the UCA's when installing longer LCA's. Mwilk012 answered yes, it's a good idea. But from reading everyone else's installs, I don't recall anyone else ever mentioning this. It sounds logical, but I wonder how necessary it is if your not extending the LCA's by much.

I swapped out my stock Sport S suspension for Rubicon Springs and Shocks with a .5 inch front spacer lift (to level out rake). I got about 1.5" lift out of it, so I intend to go with 24-1/4 as initial adjustment on the LCA's. I am currently sitting at 5.5* caster and it is a little twitchy at speed.

So with all of that said, will a slight increase in length of the LCA's require a break and re-torque on the UCA's?

I always do it on factory style bushings, but if you decide not to , don’t worry, your Jeep will not explode into flames....?....?..... and you’ll likely lift and change uppers before the oem wear out .?

 

[txj2go]

So with all of that said, will a slight increase in length of the LCA's require a break and re-torque on the UCA's?

I don't think it does. If the premise is that the control arms are put in place with the vehicle setting on the ground loaded and then torqued, so that there is no load (twist) on the rubber bushings while at rest, then yes lifting it will put some twist into the upper bushings. However the twist is only a fraction of the total twist they see when the suspension is completely flexed. Well I suppose if you don't release and retorque them then at full flex now they are twisting more than they would. So does this shorten their life enough to warrant the effort to retorque them? I don't think so but each person can make up their own minds about it. It might also depend on how well equipped you are to do the torqueing. It is a major effort for some people (like me) to torque the lower ones so I would not attempt the upper ones. If a person has the equipment to do it easily then maybe go ahead.

 

[hurricanes99]

Manufacturer (core 4x4) recommended loosening upper control arms when installing longer lowers and then torquing back to spec with Jeep under weight. Not sure if most do that or not, but that’s what they told me. Uppers looked like a pita to get access to compared to lowers.

 

[txj2go]

Manufacturer (core 4x4) recommended loosening upper control arms when installing longer lowers and then torquing back to spec with Jeep under weight. Not sure if most do that or not, but that’s what they told me. Uppers looked like a pita to get access to compared to lowers.

Thinking about this a little bit more- I'm not sure the amount of rotation from changing LCA is significant compared to other factors, so that alone I don't think would justify messing with the UCA. IOW would loosening and tightening the bolts do more harm than good.

OTOH rethinking what I said just above, the amount of change to the UCA from installing a lift is much more significant and this might be the justification for adjusting the UCA. I agree that they are probably a pain in the butt to do so I'm not planning on adjusting mine.

 

[hurricanes99]

Thinking about this a little bit more- I'm not sure the amount of rotation from changing LCA is significant compared to other factors, so that alone I don't think would justify messing with the UCA. IOW would loosening and tightening the bolts do more harm than good.

OTOH rethinking what I said just above, the amount of change to the UCA from installing a lift is much more significant and this might be the justification for adjusting the UCA. I agree that they are probably a pain in the butt to do so I'm not planning on adjusting mine.

You can't adjust your upper control arms if they are stock. Core 4x4 stated it would cause some binding of the bushing in the uppers and may result in premature wear, but i'm not sure how much were talking just by moving the lowers out a 1/4".

 

[txj2go]

You can't adjust your upper control arms if they are stock. Core 4x4 stated it would cause some binding of the bushing in the uppers and may result in premature wear, but i'm not sure how much were talking just by moving the lowers out a 1/4".

That was my point after I thought about it some more. The lowers only move out by 1/4", but for those of us who are changing lowers due to adding a lift, the uppers are moving down by 1.5-2". That's what makes the most difference in the deformation in the bushing.

 

[hurricanes99]

Another question.. so my new lca’s will help with wandering once adjusted correctly, but what would help with what I’m experiencing when I hit bridges or rough places in the road and the steering wheel shoots left or right? Sometimes it can be pretty violent. I have the newest steering damper and track bar from jeep. There is no death wobble, but it will definitely get your attention.

 

[blnewt]

Another question.. so my new lca’s will help with wandering once adjusted correctly, but what would help with what I’m experiencing when I hit bridges or rough places in the road and the steering wheel shoots left or right? Sometimes it can be pretty violent. I have the newest steering damper and track bar from jeep. There is no death wobble, but it will definitely get your attention.

Might be experiencing bump steer, more pronounced w/ taller lifts though, here's a clip explaining it

 

[hurricanes99]

Got my new adjustable LCA's off and put back on last night. The shop that had put them on for me had totally fouled everything up. They changed the length back to stock even though i had them set at 24 1/4" pre install and they mounted the adjustable end at the axle even though i asked for the opposite. One thing i can say is torquing to 190 ft lbs even with the jeep on ramps was a pita. I used all new hardware from core 4x4 and ended up having to have a buddy hold a box wrench on one side while i torqued the other. There is no way one person could do this. Makes me wonder if the stock hardware would have grabbed once it was at a certain tightness? The new hardware continued to spin regardless without holding the other bolt or nut with the box wrench. Does anyone know if it matters when torquing the nut vs the bolt? Would it be accurate either way? I had to do that on some of the fasteners. Will post back once i have had a chance to get out on the highway some.

 

[limeade]

Got my new adjustable LCA's off and put back on last night. The shop that had put them on for me had totally fouled everything up. They changed the length back to stock even though i had them set at 24 1/4" pre install and they mounted the adjustable end at the axle even though i asked for the opposite. One thing i can say is torquing to 190 ft lbs even with the jeep on ramps was a pita. I used all new hardware from core 4x4 and ended up having to have a buddy hold a box wrench on one side while i torqued the other. There is no way one person could do this. Makes me wonder if the stock hardware would have grabbed once it was at a certain tightness? The new hardware continued to spin regardless without holding the other bolt or nut with the box wrench. Does anyone know if it matters when torquing the nut vs the bolt? Would it be accurate either way? I had to do that on some of the fasteners. Will post back once i have had a chance to get out on the highway some.

Doesn't matter which fastener you hold with the wrench and which one you use the torque wrench on.

 

[blnewt]

Got my new adjustable LCA's off and put back on last night. The shop that had put them on for me had totally fouled everything up. They changed the length back to stock even though i had them set at 24 1/4" pre install and they mounted the adjustable end at the axle even though i asked for the opposite. One thing i can say is torquing to 190 ft lbs even with the jeep on ramps was a pita. I used all new hardware from core 4x4 and ended up having to have a buddy hold a box wrench on one side while i torqued the other. There is no way one person could do this. Makes me wonder if the stock hardware would have grabbed once it was at a certain tightness? The new hardware continued to spin regardless without holding the other bolt or nut with the box wrench. Does anyone know if it matters when torquing the nut vs the bolt? Would it be accurate either way? I had to do that on some of the fasteners. Will post back once i have had a chance to get out on the highway some.

With the Mopar LCAs it wasn't too tough torquing them down to 190 w/ ramps, the 150lb torque wrench I used was easy to get clicked at 150, then a 2ft breaker bar another 45 degrees with my leg pushing the bar. Maybe those aftermarket bar fasteners don't play as nice though

 

[hurricanes99]

With the Mopar LCAs it wasn't too tough torquing them down to 190 w/ ramps, the 150lb torque wrench I used was easy to get clicked at 150, then a 2ft breaker bar another 45 degrees with my leg pushing the bar. Maybe those aftermarket bar fasteners don't play as nice though

Yea maybe the fasteners had some effect. The bolt kept spinning on the washer regardless of torque... thats why i'm saying it was tough. One hand on the box wrench and the other on the torque wrench and then try to torque to 190 laying on your back pushing up.. I would like to think I'm strong, but damn that was tough..lol. Definatley helped when my buddy showed up to assist. I hope the ride is better and worth the cost and effort. I do plan to get a lift and hate the thought of removing the LCA's again to compensate for the lift height.

 

[dpike]

i just installed a steer smarts track bar, tie rod and drag link, got it pretty well set but had the wife take it up to OK4WD to get it officially alligned. i considered replacing the lower control arms with adjustables before getting it aligned, but didn't. interesting enough with the OE control arms my caster is 6.5°.

 

[omnitonic]

So does this shorten their life enough to warrant the effort to retorque them? I don't think so but each person can make up their own minds about it. It might also depend on how well equipped you are to do the torqueing. It is a major effort for some people (like me) to torque the lower ones so I would not attempt the upper ones.

I read advice to loosen the UCAs, and even the track bar, just to unbind everything. When I actually got under the Jeep to do this, I looked at everything and said nah. Nothing moved much, the fasteners would have been challenging to reach with it down on the ground, and I just installed the LCAs and called it a day.

In hindsight, I feel this was totally the right call. So far, I still don't have the LCAs up to full torque yet. I hammered them as hard as I could with my impact, then got as tight as possible with the torque wrench, but it never clicked. When you start getting up there close to 190, it's damn hard to hold onto the wrench on the far side, even when another person is just doing that one job. I'm really glad I didn't loosen any of the fasteners that would be even harder to torque.

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