TJ Shock & Spring Specification Resource Thread

Heck, that is an awful lot of sprung weight. If that is the sprung weight, how much do those TJs weigh in at in total? With 1200lbs sprung weight in the rear corners the figures quoted on page 1 for the Skyjacker 6" lift spring would only yield about a 3" lift, so what springs are these people using to run 35s or bigger?!? Are you sure you are referring to sprung weight?

But that aside, for a TJ of those epic proportions the point is both of these springs would be useless anyway, as they would be giving negative lift versus a stock TJ anyway. That is my point, in the useable range, based on the figures quoted on page 1 they seem to yield essentially the same result. That is not the case for the equivalent front springs.

You're right, I was only halfway paying attention when I posted that.

I tend to agree... The difference in rates just doesn't seem like that much considering the range of rates offered in general.

What might help inform your decision and shed light on the product intent is to approach it from the other direction - instead of finding the length of both springs at the same load, find the load of each spring that results in the same length.
 
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The problem with OME is that there are too many options. Too many options creates analysis paralysis.
It wouldn't surprise me if rockjock is getting more calls to tech service about which of two 4" spring kits to buy than they were about the one kit resulting in too much or not enough lift.
 
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The problem with OME is that there are too many options. Too many options creates analysis paralysis.
If the free length and spring rate info in the table on page 1 is correct and the give the same outcome in any realistic scenario it seems an easy choice to me, get the longer spring. It is just that I guess I am now wondering if the info in the table is right.
 
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If the free length and spring rate info in the table on page 1 is correct and the give the same outcome in any realistic scenario it seems an easy choice to me, get the longer spring. It is just that I guess I am now wondering if the info in the table is right.
How much lift do you want to achieve?
 
Mine is about 4600lbs overall with a rear corner weight no more than 950lbs.
Is that 950lbs total weight or sprung? Having had a look at your build listed on your profile theonly added weight components I can see at the back are the Exogate, New Venture rear bumper plate and bigger tire. Is that about right?
 
Is that 950lbs total weight or sprung? Having had a look at your build listed on your profile theonly added weight components I can see at the back are the Exogate, New Venture rear bumper plate and bigger tire. Is that about right?
Sprung.

That's about right. When I get aluminum corners and sliders installed, I don't expect to break 1000lb sprung per corner. If anything, I hope to be about where I am currently.
 
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Sprung.

That's about right. When I get aluminum corners and sliders installed, I don't expect to break 1000lb sprung per corner. If anything, I hope to be about where I am currently.
Thanks. Any idea how much weight those three have added? I think from a quick search the Exogate is about 50lbs, guessing the 35" spare adds maybe another 20lbs but no idea what the bumper is adding.
 
Thanks. Any idea how much weight those three have added? I think from a quick search the Exogate is about 50lbs, guessing the 35" spare adds maybe another 20lbs but no idea what the bumper is adding.
Bumper was about 25lbs.
 
If the free length and spring rate info in the table on page 1 is correct and the give the same outcome in any realistic scenario it seems an easy choice to me, get the longer spring. It is just that I guess I am now wondering if the info in the table is right.
Any chart is just a reference. Some numbers will be accurate, others not so much. Your best bet is to continue doing what you're doing, which is ask questions. If 2.5" of lift is your goal, and you don't want to go higher, you can zero in on a 2" spring and add spacers as needed to tune things. One thing to keep in mind that the original lift height will be higher, but settle once you've driven it for a little while.

Having been through this myself, the biggest challenges in your desired lift range is spring free lengths are limited, as is the ability to significantly improve shock travel.

BTW, 1200 lb per corner, as @jjvw pointed out, is excessively heavy!
 
Thanks goes out to @Fulton_Hogan for compiling all of this into a nice, easy to read (and organized) spreadsheet. I've added it to the original post for all to see.

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There were a couple of reasons for doing this.

1. There were some more stock-length springs that weren't listed and I wanted to add to the overall list.

2. Some folks may like looking these up alphabetically for comparison's sake; some folks may look them up by their free measurements or travel measurements.

After reading multiple threads on how the lengths of both spring and shock affects ride quality, I wanted to see what the OEM shock/spring measurements relationship was. Next thing I knew I was compiling all this.

I don't think this will alleviate physically installing springs, checking their travel, and then buying appropriate shocks, but it could help someone to narrow their field of search.
 
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I am trying to decide between OME light 2.5” and Currie progressive 3”. OME everything they say it is?
They’re just springs. They hold up the Jeep. If they hold it at the height you want you have a winner.