Stock Jeep LJ rear spring rate?

[NC06LJ]

Does anyone know what the stock spring rate is on an 06' LJ? Soft top, V6 with NO tow package.

We do a fair bit of camping and I'm sagging a bit in the rear. Looking to upgrade to a bit stiffer, but need a starting point.

Not sure, but I think it's in the 50's.......

Thanks for the help!

 

[nwoods]

I've got some 5" springs that I used to prevent sag in the rear of my LJ for a while. I eventually made the swap to Nth Degree spring relocation brackets and 4.5" AEV progressive rate springs, and they worked pretty darn well. However, I still have the 5" springs here if you want them. Pay for shipping and they are yours. They are red. Might be Skyjacker springs? They are virtually new.

 

[NC06LJ]

I've got some 5" springs that I used to prevent sag in the rear of my LJ for a while. I eventually made the swap to Nth Degree spring relocation brackets and 4.5" AEV progressive rate springs, and they worked pretty darn well. However, I still have the 5" springs here if you want them. Pay for shipping and they are yours. They are red. Might be Skyjacker springs? They are virtually new.

Thanks for the offer! I'm planning to do some measuring this weekend to see what I can make work. Buddy gave me a set of "take offs" from his '15 2DR Rubicon so I may get creative....

 

[KMET]

I also use Nth Degree spring relocation brackets, adds 1-5/8". (Old Man EMU 2" rear + RE 3.5" front) Quadratec still sells them for $180.

Whats your current setup?

 

[1stDeuce]

I believe the stock LJ rear spring rate is around 170lb/in, depending on what options you have. JK springs do not really fit. Nor do rear ZJ springs. You'll want to use a spring that was made for a TJ.

My best suggestion is to toss in a set of AirLift airbags. I had them in my LJ and they worked pretty well for carrying extra weight without making the ride too firm. I got five years out of the set I installed before one died. I didn't drill the hole in the lower spring pad big enough, and it would pull the hose off if I really flexed the suspension on the driver's side. If you do install bags, drill a 3/4" hole if you can. 1/2" is not quite big enough for the hose clamp, and can pull off the hose if it's not exactly centered in the hole.

You could also put a 3/4" spacer back there. That'll bump the rear up a bit, so it'll sit higher empty, but also higher loaded. (Sounds like your only complaining about loaded, making airbags a better option.)

Nth spring locators do raise the effective rate by ~5%. But they also lift it 1-5/8", which might be too much unless you want to bump the front up a bit also. I'm running them now, and am very happy with them.

OME 4162 rear springs will probably net you 1" to 1.5" on your LJ, but OME's spring rate is lower than the factory LJ rear spring rate, so overall ride quality may suffer and you'll still get noticeable sag when loaded. (Yes, the OME rate even for the HD spring is LOWER than a factory LJ spring!)

If you like your current height and ride, I would still recommend putting airbags in the back. Even just 20psi was plenty to keep the back of my Jeep from squatting when loaded, and at 5psi, you can't tell they're there. Capacity when you need it, and not when you don't.
Chris

 

[Desert Dan]

I'd get a set of Old Man Emu coils for the rear or better yet a whole suspension springs and shocks from OME. Then the suspension works together.
I think there are 3 different springs for the TJs for different weights and loads.

Get a set of front caster adjustment shims from Jeep if you need to adjust your caster.

 

[1stDeuce]

I used to be an OME fan, but I absoulutely HATE their new Nitrocharger Sport shocks. If you have a 5000lb TJ, they probably ride pretty well, but a 4000lb LJ like mine is pretty rough on the new Nitrocharger Sports. And the old shocks are discontinued.

And as stated above, OME rear springs, even the HD version, have a LOWER spring rate than the stock LJ rear springs. You'll get lift, but the spring rate is a bit softer, which is not so good if you're running heavy. The OME springs were designed long before the LJ existed, and they've not released an LJ specific spring as far as I know.

 

[1stDeuce]

Oooh, if you are stock height, here's an airbag kit off fleabay for cheap!! Looks like it's all there to me. There's an older thread on here where several people spoke up about running this kit with good results... Here. Note that the TJ airbags fit in the coil and don't really affect droop or compression at all, unlike many of the truck setups designed to work with leaf springs.

 

[comptiger5000]

If the lower spring seats are designed to accept a spring that doesn't square off or anything and just ends, you can always get a taller lift spring of a known spring rate and cut it down to your desired ride height (and calculate the new spring rate based on how much was cut).

I ended up doing this in my ZJ, as I didn't want a significant lift, but was finding the stock springs way too soft. I went with 3" Skyjacker springs up front with 2 coils cut off + an OME trim packer (sits 3/8" - 1/2" taller than stock) that gave a ~280lb/in spring rate compared to the stock 190. For the rear, I used the stock front coils with 2.25 coils cut off (sits 1/2" - 5/8" taller than stock unloaded), giving a ~260 lb/in spring rate compared to 160 for the stock coils.

I'll probably end up changing springs again once I've gone through and changed everything else I want to in the suspension, but it works well as-is. The ride quality is barely any worse than stock (and better than stock springs with Procomp MX6 shocks). I'm running Bilstein 7100s, valved 400/100 in the front, 360/80 in the rear. Rebound damping is pretty much spot on for both ends, although I really need to tweak the compression damping a bit (front needs more high speed compression damping as it's too easy to bottom on big hits, the rear needs a little less low speed compression damping as I get a little bounce in the tire sidewalls over certain small bumps if I'm driving unloaded, which it is in normal DD duty).

 

[jscusmcvet]

Great discussion on this. Please let us know what you go with and how it works out.

 

[KMET]

Rear, OME-942 2" springs & Nth Degree spring relocation brackets

Front, Rubicon Express 3-1/2"

 

[NC06LJ]

Thanks for the help fellas!

Right now I'm running a 2in BB with 2in "junkyard" springs I sourced. I just finished the RE adjustable control arms front and rear with the currie curectlync tie/drag combo. Not looking for much more lift (don't want to increase my center of gravity) just a bit more stiffness in the rear.

Unloaded it'll ride like a brick, but it's a purpose built jeep after all!

Got a free set of "58" rate JK Rubi spring and shock takeoffs I may play with, but I've also heard Superlift 556 springs may be a good option too.......

Time will tell!

 

[NC06LJ]

View attachment 291955

Rear, OME-942 2" springs & Nth Degree spring relocation brackets

Front, Rubicon Express 3-1/2"

Great looking ride height!

 

[comptiger5000]

Unloaded it'll ride like a brick, but it's a purpose built jeep after all!

This depends a lot on the shocks. Mine rides great up front, but just a little harsh in back when unloaded. Adding a little weight (like 1 person in the back seat) fixes it. When I had the old stock springs / MX6 shocks setup, it rode like a log truck unless there was 300+ lbs in back.

 

[NC06LJ]

I've got some 5" springs that I used to prevent sag in the rear of my LJ for a while. I eventually made the swap to Nth Degree spring relocation brackets and 4.5" AEV progressive rate springs, and they worked pretty darn well. However, I still have the 5" springs here if you want them. Pay for shipping and they are yours. They are red. Might be Skyjacker springs? They are virtually new.

Sent you a PM