TJ Shock & Spring Specification Resource Thread

Those dumb MetalCloak 4.5” fronts go solid at 8” not 9.5”, also free length is 23.75“ not 24”

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This is for the front, but what about the rears? I'm happy to update the info (which I've done now for the fronts), but if you have info for the rears that would be appreciated too.
 
This is for the front, but what about the rears? I'm happy to update the info (which I've done now for the fronts), but if you have info for the rears that would be appreciated too.
FL 20” solid 6.75” per their website.
 
@Chris I can fill in gaps on the stock springs if you want to add to the opening post to make it easier to locate...

The Moog front spring for the non Rubicon 4.0l is the 3224
Free Height 16.39"
Install Height 11.00"
Spring Rate 134lb / inch
Stock Load 719lb per spring

The Moog front spring for the Rubicon 4.0l is the 3226
Free Height 17.25"
Install Height 11.00"
Spring Rate 134lb
Stock Load 834lb per inch

The Moog rear spring for the non Rubicon 4.0l is the 3229
Free Height 11.28"
Install Height 8.00"
Spring Rate 200lb / inch
Stock Load 653lb per spring

The Moog front spring for the Rubicon 4.0l is the 3227
Free Height 12.11"
Install Height 8.00"
Spring Rate 200lb
Stock Load 821lb per inch

Some of that is already in the table already, but I thought better to give it in one go to make it easier for people to see.

Knowing the stock load is helpful if, like me, you have a stock TJ as it means you have a known starting point to base lift calculations on.
 
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@UKTJ, tell me if I got the specs right for the Moog 3224 springs in the chart. I just added them.
 
@Chris I can fill in gaps on the stock springs if you want to add to the opening post to make it easier to locate...

The Moog front spring for the non Rubicon 4.0l is the 3224
Free Height 16.39"
Install Height 11.00"
Spring Rate 134lb / inch
Stock Load 719lb per spring

The Moog front spring for the Rubicon 4.0l is the 3226
Free Height 17.25"
Install Height 11.00"
Spring Rate 134lb
Stock Load 834lb per inch

The Moog rear spring for the non Rubicon 4.0l is the 3229
Free Height 11.28"
Install Height 8.00"
Spring Rate 200lb / inch
Stock Load 653lb per spring

The Moog front spring for the Rubicon 4.0l is the 3227
Free Height 12.11"
Install Height 8.00"
Spring Rate 200lb
Stock Load 821lb per inch

Some of that is already in the table already, but I thought better to give it in one go to make it easier for people to see.

Knowing the stock load is helpful if, like me, you have a stock TJ as it means you have a known starting point to base lift calculations on.
Stock load per inch scattered throughout ought to read as corner sprung weight.
 
I hope this is helpful. Just don't waste time tuning the ride quality with springs. Get the ride height and free length you need and move on to the shocks.
Do you have any idea how much is the weight of the 2.4l engine?
I am trying to figure out which Old Man springs to use. but every info I find is about the 6 cylinders.

I want to do a 2" lift (31" tires KO2s), Old Man springs, Rancho shocks.

Front: Stock front bumper, 4 cylinder, winch (installed only for trips).
Rear: no rear seats, soft top, 31" spare, aftermarket bumper (around 50 pounds)

* I have the budget to do the lift, but I cant figure out which springs to buy.
 
Do you have any idea how much is the weight of the 2.4l engine?
I am trying to figure out which Old Man springs to use. but every info I find is about the 6 cylinders.

I want to do a 2" lift (31" tires KO2s), Old Man springs, Rancho shocks.

Front: Stock front bumper, 4 cylinder, winch (installed only for trips).
Rear: no rear seats, soft top, 31" spare, aftermarket bumper (around 50 pounds)

* I have the budget to do the lift, but I cant figure out which springs to buy.
No idea
 
Do you have any idea how much is the weight of the 2.4l engine?
I am trying to figure out which Old Man springs to use. but every info I find is about the 6 cylinders.

I want to do a 2" lift (31" tires KO2s), Old Man springs, Rancho shocks.

Front: Stock front bumper, 4 cylinder, winch (installed only for trips).
Rear: no rear seats, soft top, 31" spare, aftermarket bumper (around 50 pounds)

* I have the budget to do the lift, but I cant figure out which springs to buy.
I have been trying to get the corner load for my 4.0, but no luck. I have emailed a couple of companies that sell the springs, but I have had no answers. My guess is therefore they don't know either or they consider it a secret they do not want to reveal.
 
I have been trying to get the corner load for my 4.0, but no luck. I have emailed a couple of companies that sell the springs, but I have had no answers. My guess is therefore they don't know either or they consider it a secret they do not want to reveal.
I think I am gonna go with the light duty OME springs for my 2.4L. fingers crossed it will be enough
 
Anyone know the rate of the upper portion (extension spring) of the Metalcloak springs?
If I had to guess, the rate is the same as the rest of the spring. But because the windings are closer together, that section reaches bind before the rest of the spring. Currie rears do something similar for a couple wraps, just not as ridiculous as Metalcloak.
 
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If anyone does, I think it would be @StG58 , but I seem to recall him saying that he tried to get them and couldn't.

Edit: Yes, I see that @Irun said they won't release the specs.

I don't think @StG58 is active on here anymore. He used to be very active but that was a long time ago.

Pretty sure we all pissed him off with our constant 2.5 bashing :LOL:
 
You will probably find it difficult to get spring rates for any of the dual rate spring manufacturers as they consider this proprietary information including Currie/RockJock.
 
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To be honest, as nobody appears to know the weight being applied to a springs by a stock TJ as a base to work from it seems of limited value to me. Yes, after installation I guess you can say ‘aha, if the published spring rate is accurate, given the free height and installed height on my TJ I now know the sprung weight at each corner is xxx’. But it seems a bit late at that stage to me.

It appears the only approach one can take is to pick a spring that seems about right from a company you like, fit it and if it doesn’t give the desired result stick in some spacers or buy some different springs and try those.
 
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I don't think @StG58 is active on here anymore. He used to be very active but that was a long time ago.

Pretty sure we all pissed him off with our constant 2.5 bashing :LOL:
Yea, I wrote to him recently with a question, and he mentioned that 2020 was quite a year for him so hadn't been on much. He came back on for a bit after that, and hopefully he'll be around more. I've benefitted from all his 2.5 information. And of course I need him to stick around to carry the brunt of the 2.5 bashing for me. ;-)
 
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