Suspension Setup Questions

Bradjh122

Bradjh122

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Hi everyone. I have a 2004 Wrangler Rocky Mountain Edition. This is not my first project car but it is my first Jeep, so I'm still somewhat new to the Jeep community.

When I purchased the Jeep back in August 2020, it had a 2.5" Rough Country suspension lift on 31s. It's done the job for the year or so I've had the Jeep and hasn't given me any issues on the handful of wheeling trips I've been on. But it is time to upgrade. My long-term plan is to get up to 35s but I know I need to build my axles and drivetrain to be able to support 35s. That is a lot of work and money so I'm doing it in stages. This year my goal is to rebuild the suspension while staying on 31s. My shocks support up to 4.5" of lift and my control arms support up to 6". So down the road when I'm ready, I will just need to get taller springs if I need more lift to clear 35s.

Here is a list of what I've purchased so far for my winter overhaul.
  • Rubicon Express 3.5" Front Coil Springs (RE1363)
  • Rubicon Express 2.5" Rear Coil Springs (RE1314)
  • Fox 3"-4.5" Front 2.0 Performance Series Shocks (985-24-108)
  • Fox 2.5"-3.5" Rear 2.0 Performance Series Shocks (985-24-112)
  • Rock Jock Johnny Joint Control Arms (CE-9100AS)
  • MetalCloak Universal Adjustable Bump-Stop system (7040)
  • MetalCloak DuroSpring Replacement Bump Stops (7219)
  • ORO SwayLOC (SL-TJLV)
  • Ball Joints, Wheel Bearings, Brakes, Axle Seals, Other odds and ends to replace while working through the job.
I know there is still more to get, but this is what I have as of now.

The first question I ran into last weekend has to do with the springs. I took the Dana 30 front axle out, painted it, replaced all the ball joints, control arm bushings, wheel bearings, outer axle seals, and just cleaned up the whole axle. When putting the axle back in, everything went smooth until I got to the springs. I did notice the new 3.5" Rubicon Express springs were much shorter than the old 2.5" Rough Country springs out of the Jeep. When I put the Rubicon Express springs in, they just slid right in with absolutely no tension at all. There is almost three inches from the top of the spring to the top of the spring tower (See attached before and after photos).

I set my new control arms to the same length as the rough country ones that I took out but added about 1/4 inch in length to give me a good starting point that accounts for the additional lift (the guy at the local alignment shop recommended I do that). What might be the cause of there being so much gap? Is this not even an issue and I'm worried about nothing? Any input you all have would be greatly appreciated!

I also wanted to start this thread as a general discussion of everyone's thoughts and recommendations on what else I should do. As I said, this is not my first project car but it is my first Jeep so I'm trying to absorb as much information as I can.

Thank you!

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Did you measure spring height before taking the old ones out? Did you measure new ones after putting them in with the weight of the jeep on the springs? What were the free lengths of each spring?
 
hosejockey61 said:
Did you measure spring height before taking the old ones out? Did you measure new ones after putting them in with the weight of the jeep on the springs? What were the free lengths of each spring?
Click to expand...
I did not measure the spring high of the old ones with the weight of the vehicle on them. I can put them back in and get that measurement.

I also just got the jeep back on its wheels last night so I can grab the measurement of the new springs with the vehicle weight on them.

When I have them out, I can get measurements of both sets without any weight on them. I do know that the new rubicon express springs were at least 2" shorter than the old rough country ones.
 
Also, I dont see a track bar or steering setup up in the first picture, so your axle is seeing a bit more droop. Hook those up and then cycle your suspension.
 
tworley said:
Also, I dont see a track bar or steering setup up in the first picture, so your axle is seeing a bit more droop. Hook those up and then cycle your suspension.
Click to expand...
Thank you, @tworley. I didn't know the axle would droop more without those connected. I will get those connected tonight and see if it makes a difference.
 
Bradjh122 said:
Thank you, @tworley. I didn't know the axle would droop more without those connected. I will get those connected tonight and see if it makes a difference.
Click to expand...
Its still early and I havent had coffee--you wont be able to cycle your suspension with the coils in place, but if your trackbar gets installed that will still limit the amount of droop your axle sees.
 
Sway bar is connected in the before picture, but not the after. That would account for the axles droop
 
tworley said:
Its still early and I havent had coffee--you wont be able to cycle your suspension with the coils in place, but if your trackbar gets installed that will still limit the amount of droop your axle sees.
Click to expand...
I knew what you meant. I still need to pull the coils and cycle the suspension to get my bump stops set up. Just been waiting on parts to come in. I will get the track bar and steering components in tonight with the coils still in and see if it reduces the gap.

That leads me to another question I had. Since I did go up in lift, do I need to install a drop pit arm?
 
Ovaltine said:
Sway bar is connected in the before picture, but not the after. That would account for the axles droop
Click to expand...
I did think about that as well. I upgraded to the SwayLOC system and haven't had a chance to install it yet. I will try to get it in soon to see how much it brings the axle up.
 
"I set my new control arms to the same length as the rough country ones that I took out but added about 1/4 inch in length"
This is fine for a starting point. Just keep in mind that the advantage of the adjustable control arms is the ability to control your caster angle in the front (also pinion angle in front but not as much issue there) and your pinion angle in the rear. Lots of info on those topics in this forum. maybe start here: https://wranglertjforum.com/threads...-control-arms-on-a-jeep-wrangler-tj-lj.17062/

"I also wanted to start this thread as a general discussion of everyone's thoughts and recommendations on what else I should do. As I said, this is not my first project car but it is my first Jeep so I'm trying to absorb as much information as I can."
Just to be ready for it, go ahead and look at options for a SYE set up on your transfer case and the CV driveshaft to go with it if you don't already have it. You might not need it but it's usually at 2.5-3" lift that driveline vibrations start. Other budget options are transfer case lowering and motor mount lift but they have their limitations and it all depends on whether you want to use your jeep for.
Also, what kind of track bar set up do you have? With your previous lift, you might just have a bracket on the axle to raise the mounting point, or nothing extra at all. As you get closer to 4" lift the stock trackbar starts to really pull your axle to one side when the suspension extends and the adjustable will allow you to dial it in. Lots of info in the forum on that too.


"do I need to install a drop pit arm?"
Nope


And know that your quest for 35's has opened pandora's box and you'll lose at least a month of your life on this forum scouring for answers to questions you never knew you would have. Never trust one answer as final (including mine), leverage the consensus of the group, and learn the names that actually have the most knowledge so you can watch for their input.

https://wranglertjforum.com/threads/so-you-want-to-run-35-tires-on-your-tj.2428/
 
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