Fitting 37"s - 3.5" Coil lift w/ factory control arms vs. Long arms

So I was reading in the "newbie" suspension thread from a few years back and it was very helpful for the builds I have coming up. I do want some clarity around the question and answer below, though.

"Q: At what lift height would I want to consider a Long Arm kit?
A: On a Jeep JK Wrangler, you can safely run factory length arms up to about 4" of lift and without significant effect. However, you can benefit from the suspension geometry correction long arms provide at 3.5" of lift."

In the next few weeks, I am putting in a 3.5" RK coil spring lift (with all necessary components - i.e. longer brake lines, rear sway bar links, je reel front driveshaft, 2" bump stops). I am also putting on 37" nitto trail grapplers about a week later. However, I am not doing anything to my factory control arms because I'm saving up for RK's X-Factor long arm kit around the end of the year. My question is - when the answer above states I can safely run factory length arms up to 4", does that mean I can use the factory control arms? Or is it implying I can run factory lengths, but need upgraded arms that come with the short arm kits, etc...

Like I said, I'm going long arms in the next 6 months - but want to make sure I can still go wheeling on 3.5" and 37's on factory control arms, in the meantime. Understood this has probably been asked before, but I would appreciate any help/input/experiences.

Thanks!
 
R

RockyMtnAnvil

Guest
I would suspect that you would, at least temporarily, want to run some drop brackets or adjustable control arms to correct caster/pinion.
 

cozdude

Guy with a Red 2-Door
You can run the factory arms. The only arms you will need to change is the front lowers to adjust caster and the rear uppers if you have a 2 door or 4 door with an aftermarket driveshaft.
 
You can run the factory arms. The only arms you will need to change is the front lowers to adjust caster and the rear uppers if you have a 2 door or 4 door with an aftermarket driveshaft.

Ah, I was really hoping to get by with the factory arms until long-arms. The only reason I decided to do the 3.5 coil springs first was because after I installed my PR44, my adjustable track bar was hitting up against the front of the pumpkin with enough up and down travel (currently on 2.5" BB that has sunk quite a bit). So I needed to get more clearance immediately. If that rubbing wasn't happening, I would have just done the coils and long-arms all at once. Ugh, I might just wait it out and see how the driving feels after getting these coils in before pulling the trigger on more arms, just to swap them out again in 6 months. Thanks for the feedback though!
 

cozdude

Guy with a Red 2-Door
Ah, I was really hoping to get by with the factory arms until long-arms. The only reason I decided to do the 3.5 coil springs first was because after I installed my PR44, my adjustable track bar was hitting up against the front of the pumpkin with enough up and down travel (currently on 2.5" BB that has sunk quite a bit). So I needed to get more clearance immediately. If that rubbing wasn't happening, I would have just done the coils and long-arms all at once. Ugh, I might just wait it out and see how the driving feels after getting these coils in before pulling the trigger on more arms, just to swap them out again in 6 months. Thanks for the feedback though!

Since you don't have an aftermarket rear driveshaft and you have a 4 door you don't need rear upper arms. Only the front lowers for caster adjustment.
 
Since you don't have an aftermarket rear driveshaft and you have a 4 door you don't need rear upper arms. Only the front lowers for caster adjustment.

Okay, that's what I'll do then. Thanks for the advice. Anyone in the market for adjustable front lower control arms, message me in November HA!
 

olram30

Not That Kind of Engineer
I would NOT get geometry correction brackets. Think of it this way. You lift you jeep to get it away from the ground. All these do is lower the arms back down and put them back in harms way and make it so you don't have as much clearance.

I agree. Just a good quality set of lca's is all that's needed.
 
I would NOT get geometry correction brackets. Think of it this way. You lift you jeep to get it away from the ground. All these do is lower the arms back down and put them back in harms way and make it so you don't have as much clearance.
That makes sense. I'm already having clearance issues with my pumpkin and front track bar. These brackets may defeat the purpose of the lift. I'm just gonna get the RK front lowers for now and have them put in with the coils. I'll find a home for them later after I go long arms.
 

cozdude

Guy with a Red 2-Door
That makes sense. I'm already having clearance issues with my pumpkin and front track bar. These brackets may defeat the purpose of the lift. I'm just gonna get the RK front lowers for now and have them put in with the coils. I'll find a home for them later after I go long arms.

Is there a reason why you want to go long arm? Tons of people stay with factory arms and front lower adjustable arms at that height
 
Is there a reason why you want to go long arm? Tons of people stay with factory arms and front lower adjustable arms at that height

Yea, I hear ya. I'm sure lower fronts is all I would need. But I have the image of A jeep I want built in my head (and on paper) and won't stop until I get there lol. Just taking it in one step at a time. That's why I'm psyched I joined this forum because I was hoping to get a lot of good feedback. And I already have for sure.
 

mastrcruse

New member
I've driven 6000 miles on factory arms, 22000 miles on an RK Mid-Arm kit, and 2000 miles on a RK X factor long arm kit. Some thoughts I have around it is that the mid-arm Kit wasn't totally necessary but rode better than stock. Majority of this improvement was the springs and shocks though. The long-arm Kit is a great improvement and really smooths out the ride of the jeep. It really floats like a Cadillac over things but some people think it feels a little squishy in the rear. I do have less bind within my articulation range which smooths the motion out, however, I'm still very limited by my shocks which need to be changed.

If youre dying to spend money and can afford it, go long arms and don't waste your money "in the middle". I love the improvement and am glad I upgraded. If you don't want to make that jump, stick with the stock stuff or maybe replace the lowers and see how you like it. Some of the biggest factors with ride is shocks, springs, tire pressure so get those in check too.
 
I've driven 6000 miles on factory arms, 22000 miles on an RK Mid-Arm kit, and 2000 miles on a RK X factor long arm kit. Some thoughts I have around it is that the mid-arm Kit wasn't totally necessary but rode better than stock. Majority of this improvement was the springs and shocks though. The long-arm Kit is a great improvement and really smooths out the ride of the jeep. It really floats like a Cadillac over things but some people think it feels a little squishy in the rear. I do have less bind within my articulation range which smooths the motion out, however, I'm still very limited by my shocks which need to be changed.

If youre dying to spend money and can afford it, go long arms and don't waste your money "in the middle". I love the improvement and am glad I upgraded. If you don't want to make that jump, stick with the stock stuff or maybe replace the lowers and see how you like it. Some of the biggest factors with ride is shocks, springs, tire pressure so get those in check too.

Good stuff, thanks man. I'm not dying to spend money, but just trying to build the best jeep I can without having to do too many things twice...already done that lol. Think I'm just going to replace the front lowers while I save for the long arms.
 

mudmobeeler

Caught the Bug
What kind of joints do they use?

Quoted from their website "2-1.25" Cryo and Heat Treated Chromoly Heim Joints with Jam nuts and Misalignments for 9/16" Bolt. Flexible yet durable Poly bushings are included as well with the inner sleeve for a 9/16" Bolt."

I have no experience with RK but it seems like people on here had issues with their kits causing the rear spring to bow and other rubbing issues. I honestly dont remember what kit of theirs it was though. Just saying do your research thoroughly.
 
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Quoted from their website "2-1.25" Cryo and Heat Treated Chromoly Heim Joints with Jam nuts and Misalignments for 9/16" Bolt. Flexible yet durable Poly bushings are included as well with the inner sleeve for a 9/16" Bolt."

I have no experience with RK but it seems like people on here had issues with their kits causing the rear spring to bow and other rubbing issues. I honestly dont remember what kit of theirs it was though. Just saying do your research thoroughly.

I did end up going with the RK front lowers. I have the RK adjustable front and rear track bars and they're pretty solid. Yep, I've totally read some poor reviews...then I've read a lot of really really good ones also. I feel like with so many jeep owners out there, you're going to have your haters of one brand or another. I'll be going to evo bolt in king coilovers in the new few years, which will solve all of this anyways :)
 

mastrcruse

New member
Good stuff, thanks man. I'm not dying to spend money, but just trying to build the best jeep I can without having to do too many things twice...already done that lol. Think I'm just going to replace the front lowers while I save for the long arms.

Great idea. From my experience with the 3 different setups, long arms should be the end goal. Your plan is a good one.
 
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