Questions about installing 4" springs

Kaptainkid1

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I just purchased 4" lift pro comp springs and lower track bars.

Can I install the 4" lift springs and 4x pro comp for front and rear lower track bars arms without any other parts or mods.

Currently the Jeep has stock lower track arms and upper Track bars arms. Since this is a used Jeep with mods done by the last owners. I'm in the process of upgrading and fitting better parts and continuing the mods to have this Jeep to be nicely modded Overland reliable rig.

The upper track bar arms are oem stock stamped metal frames. Since I don't have the upper track bars arms yet. I'm still shopping for used adjustable upper track bars arms. Can I run a mix lower pro comp track bar arms and upper stock track bar arms? Until I find my next upper arms deal. May be 6 month or year before these parts are found and upgraded to my Jeep Rig.

I was going to Keep the Rough Country shocks. I assuming Rough Country 3.5 shocks should be fine even with a 4" lift spring.

Do I need to run 4" lift shocks too or that's not necessary?
 
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4" springs will give too much lift height for your rear driveshaft to operate with without creating major vibrations. You either need shorter springs or an aftermarket rear double-cardin driveshaft together with a slip yoke eliminator kit for your transfer case.
 
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4" springs will give too much lift height for your rear driveshaft to operate with without creating major vibrations. You either need shorter springs or an aftermarket rear double-cardin driveshaft together with a slip yoke eliminator kit for your transfer case.
The Jeep is running fine with 3.5" Rough Country lift kit. I believe the lift kit came with 3.5" Shocks, rear trailer arm adjustment, and 3.5" lift springs.
1/2" increase adjustments can make that much of a difference? I've read people running 4" lifts and not running SYE.
I did want to buy SYE kit but it's not in the budget right now but seems it's my next purchase.
Can I at least install the lower control arms and pull of the crappy OEM stamped control arms. I think that doesnt change alignments.
 
You can run 4" of suspension lift with the LWB Unlimited without a SYE and DC driveshaft but not with the SWB standard TJ Wrangler. At least not without a stupid deep 2" tcase drop plus a set of 1" tall motor mount lifts. Yes that 1/2" height difference can be a make or break difference. I wouldn't recommend those 4" springs without doing what's needed to make things work right.
 
Putting D.S. problems aside, if your lower adjustable arms can be set to the same length as the ones you are replacing then in theory all would be fine while you hunt down your upper arms. I would suggest keeping the same springs in until that point though. Because that extra 1/2"(or more if the current springs have some sag) could trigger those drive line problems Jerry is telling you about. What might be best is to wait until you have gotten all your parts together and then do it all at once.
 

I just watched this Extreme Terrain 4"lift kit from Rough Country. It's a DIY video from a known 4x4 company ExtremeTerrain.com. This Jeep TJ mod was done to a stock Jeep. Running no SYE. So my used pro comp parts seem to be the missing puzzle to complete my 4" lift kit with proper parts from this DIY.
From what I gather I have the 1.5 inch transfer case drop installed already and the rear 2 inches track bar riser.
The only missing Part from this video is the stick shift drop linkage. Which I can fabricate that part from scrap metal plate.
So here is the mash up that I can save from both Rough County lift. 3.5" lift shocks, 1.5 inches transfer case drop spacers, the rear track bar riser.
I will replace the stock oem lower control arms all with 4x pro comp lower control arms and 4" pro comp springs, the longer rear sway bar link from pro comp, fabricate the stick shift drop linkage plate.
The only thing I don't understand is the track bar is relocated 3/4 inch to the right can be view at 19.00 min mark on video. I will do this mod but I assume it puts the track bar links back to correct geometry.?
I just checked my rig and it seems it has a adjustable track bar maybe I can make up the 3/4 in with adjustments and not drill. Check photos.
I feel I have the correct parts and a complete kits on the mash up. I'm hoping I don't get any driveline vibration.
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An adjustable track bar up front is better than moving the hole 3/4". The hole that gets drilled when using the stock track bar weakens the mount.
 
You need to tighten the jam nut on that track bar before you have a new issue.
Yeah saw that last night 1st time. Did it already.
Buying a modded used rig I'm finding little adjustments and issues that need addressing. Still trying to change all the tranny and diff's fluids. Next radiator hoses and radiator fluid. I want to zero out all the maintenance so I know I have a starting point. Jeep didn't have any maintenance records. Like many modded Jeep you find short cuts, surprises, good and bad.
 
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That is one of the advantages of finding a stock, or close to stock vehicle. While a modded one may already have many of the parts you want to add, the amount of cobbing is a concern.
 
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For me it's about the end result 35" tires. I have a long way to go. Gearing, body lift 1", lockers, Dana 44 up front....
Some things I would suggest having read what you are planning. If you go to 4” springs and no SYE/DC, go ahead and get a 1” MML to help with driveline angles. Do the 1” BL at the same time to save some trouble. You’re going to have to keep your TCase drop for awhile. Get some Rancho 5000x shocks. You can thank me later
 
Some things I would suggest having read what you are planning. If you go to 4” springs and no SYE/DC, go ahead and get a 1” MML to help with driveline angles. Do the 1” BL at the same time to save some trouble. You’re going to have to keep your TCase drop for awhile. Get some Rancho 5000x shocks. You can thank me later

I will do the SYE for sure its definitely on my list of mods. More than likely the next major mod for sure. Tires are last of course but I want 5x beadlock steelie pro comp 17". This past weekend I put on my lower control arms backward of course because I couldn't finding anything online on the direction the arms should be installed until I finished installing the c-arms. Following day pulled it apart and did the all over again.
Happy with the results car tracks better on the road noticed the old rubber bushing old arms we're on the way after replacing parts. I guess 17 years on stock parts is a good time to replace rubber anything.
For a reference the long length of the track arms should tie into the axles for front and rear.


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I will do the SYE for sure its definitely on my list of mods. More than likely the next major mod for sure. Tires are last of course but I want 5x beadlock steelie pro comp 17". This past weekend I put on my lower control arms backward of course because I couldn't finding anything online on the direction the arms should be installed until I finished installing the c-arms. Following day pulled it apart and did the all over again.
Happy with the results car tracks better on the road noticed the old rubber bushing old arms we're on the way after replacing parts. I guess 17 years on stock parts is a good time to replace rubber anything.
For a reference the long length of the track arms should tie into the axles for front and rear.


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Now you're going to need some bigger tires to go with that lift!