Most common 2-2.5" inch lift

My plan is for 31" tires, so I dont think I care very much for 2.5" over 2". right? I think I should use spacers only for the possible rake and not for additional height.

I am not really sure, if I should use the light or the hard duty springs though. Do they both give the same lift? or light gives 2" and hard 2.5"?

Thanks
Not sure if you have seen the new spring and shock resource thread or my spring calculation posts, but if my logic is sound you should be able to get a good idea of what ou will get with justa few pieces of information.

I think your 2004 4 cylinder will have been specified with Moog 3228 in the front. See this link for useful information about those springs and a stock 4 cylinder TJ: https://www.shockwarehouse.com/site...me/Moog-3228-Front-Constant-Rate-Coil-Springs

You can see the free height is 16.2" and the spring rate is 124lb per inch. The load per corner (I assume for a stock TJ) is quoted as 650lb. That gives 650 / 124 = 5.2" of compression in the spring. That takes the 16.18" spring down to 10.94" which ties in with the quoted install height for the spring of 11.0".

If you replace that spring in a stock 4 cylinder TJ with an OME2932 (light weight) you have a free height of 18.5" and a spring rate of 140lb per inch. So with a stock TJ corner load of 650lb you get compression of 4.6" and therefore an install height of 13.6", which is 2.6" over the stock 11.0" install height. But, your TJ may not be stock, if you have added weight to the front, say a winch, you will need to increase the load per corner accordingly and recalculate.

You can do exactly the same for the rears.
 
Not sure if you have seen the new spring and shock resource thread or my spring calculation posts, but if my logic is sound you should be able to get a good idea of what ou will get with justa few pieces of information.

I think your 2004 4 cylinder will have been specified with Moog 3228 in the front. See this link for useful information about those springs and a stock 4 cylinder TJ: https://www.shockwarehouse.com/site...me/Moog-3228-Front-Constant-Rate-Coil-Springs

You can see the free height is 16.2" and the spring rate is 124lb per inch. The load per corner (I assume for a stock TJ) is quoted as 650lb. That gives 650 / 124 = 5.2" of compression in the spring. That takes the 16.18" spring down to 10.94" which ties in with the quoted install height for the spring of 11.0".

If you replace that spring in a stock 4 cylinder TJ with an OME2932 (light weight) you have a free height of 18.5" and a spring rate of 140lb per inch. So with a stock TJ corner load of 650lb you get compression of 4.6" and therefore an install height of 13.6", which is 2.6" over the stock 11.0" install height. But, your TJ may not be stock, if you have added weight to the front, say a winch, you will need to increase the load per corner accordingly and recalculate.

You can do exactly the same for the rears.
Hey! I just saw that. It was quite helpful. Thanks!

One question to begin with:

The Load per corner is quoted as 650lb for the 4 cylinder or the 6 cylinder?
 
I am real happy with the Zone 2 1/2 lift I installed in 2019, made the ride much better and gave me room for 33"s.

IMG_1981.webp
 
Hey! I just saw that. It was quite helpful. Thanks!

One question to begin with:

The Load per corner is quoted as 650lb for the 4 cylinder or the 6 cylinder?
I would say the 4 cylinder as there is a different spring that says it is for the 6 cylinder and shows a higher weight. However, I have a general concern over these load figures. The specification shown on the 6 cylinder springs in terms of free height and spring rate gives an install height of 11" when the load is applied, but I am told by others on here the install height for a stock TJ is 12", so if the free height and spring rate are right, it either means the load is wrong or these are nor direct OEM replacements. I need to know which of these explanations it is before I can have confidence in the quoted loads.
I have emailed Moog with a question on this and will report back if and when I hear from them.
 
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