Originally Posted by sideshowbob

Thanks to all you posted and added valuable info. I was originally going to go with 35" and 2.5 lift but after much reading and studying I thought what better suit my driving was 33" tires. I didn't like the way the JK road,too soft and swaying and after seeing these post I saw I had 13 fronts and 55 rear. I was able to find 17 fronts and 59 rears for less than $100 shipped. Added 1.5" spacers and Nitto Terra G2 285/70-17 and I'm very happy on how it rides even with stock shocks but will be changing those soon

Originally Posted by sideshowbob

Thanks to all you posted and added valuable info. I was originally going to go with 35" and 2.5 lift but after much reading and studying I thought what better suit my driving was 33" tires. I didn't like the way the JK road,too soft and swaying and after seeing these post I saw I had 13 fronts and 55 rear. I was able to find 17 fronts and 59 rears for less than $100 shipped. Added 1.5" spacers and Nitto Terra G2 285/70-17 and I'm very happy on how it rides even with stock shocks but will be changing those soon

Originally Posted by BoTurk

I've read all 80+ pages of this thread. Thank you all for the info and education.

I have a 2015 Willys 2 door with 14/55 springs. I just got a set of 18/59's from the dealership off of a JKU Rubicon. This is my first Jeep and will be my first "major mod."
- I already have the red rubi shocks since it's a Willys. So I should be able to just switch out the springs without changing anything else, correct?
- Should I get an alignment after doing this switch? If so, immediately after or after a few weeks?
- I read someone did this switch and it moved their steering wheel and axle out of center. Not sure I understand this, but is that something I should be concerned about.

I'm just looking for a little lift to differ from completely stock look. Will add either 33" to 35" tires and wheel spacers when the stock tires need replaced. Don't do much off road, but some back road and Illinois snow. Would be interested in some light trails at some point.

Thanks again everyone.

Originally Posted by Cobalt

I have a brand new 2012 rubicon suspension, springs and shocks that I am going to give to a nephew to install on his 2013 sahara. My question is, if there is anything that needs to be done or added to get this to fit. It will slightly lift the jeep and stiffen it, but was wondering if there is anything else that needs to be done or purchased to go along with it. I am going to install it myself. I was thinking of adding a 1" quadratech spacer to the front and a half inch spacer to the back for some added lift. I know it will need an alignment afterwords, but was wondering about driveline issues brakeline issues etc. thanks in advance

Originally Posted by zstairlessone

Check the spring numbers, no sense going through the spring change for the same set. The shocks will make a difference even if you don't upgrade the springs.

Originally Posted by Pylot7

Hey Everyone! As many of you have discovered there are several different front springs and several different rear springs and many combinations that come on the different models.

There are a couple of significant differences however and if we were to work together we can quickly figure out what matters.

I have discovered that depending on the fourth digit in your VIN that you either have a Jeep rated for 4000 to 5000 pounds Gross Vehicle Weight or for 5000 to 6000 pounds gross vehicle weight.

If you have an F in the fourth position of your VIN you have the 4000 to 5000 pound GVW machine. If you have a G then you have a 5000 to 6000 pound GVW machine.

The difference is all in the springs. It may also be in the shocks as there are several part numbers for the shocks and it may be that they actually changed the valving slightly to get the shock/spring combo working right. Putting the heavier springs on your Jeep will yield a benefit in reduced sagging when you add some weight.

Some of you have done a budget boost by putting 4 door springs on your 2 door. But I can also tell you that some of the 4 door vehicles have the same lightweight springs that I had on my low end X. So you don't automatically get the benefit of a higher spring rate with all 4 door take off springs.

If we can figure out which part numbers come with the "G" version of the Jeep then you can know that you will get a significantly stiffer spring or possibly no benefit at all.

It has largely been a crap shoot to this point. But I would like to propose that you post to this thread only the following:

1 - Your Jeep Model: X, Unlimited or Rubicon 2 door or 4 door
2 - Heaviest top you got the jeep with
3 - Your Front Left Spring Number (all jeeps have one number higher on the left than the right to account for drivers side gas tank weight)
4 - Your Rear Spring Number
5 - Your Shock Part Number only if Red/Rubicon shocks, if Black just say black.
6 - The fourth Digit in your VIN: either F or G
7 - Year of the Jeep

Every time you post I will copy your post and edit in the spring numbers on the post following this one.

I will start the list with a set of take offs that came from a four door Rubicon that was the 5-6K GVW type.

Once we get the point at which we know the minimum of the heavies for the 5-6K machines and the maximum of the lighter springs for the 4-5K machines we will have some useful information for those of us wishing to upgrade on the cheap!