Which OME springs should I go with?

The good thing about choices with the OME springs is you can fine tune. OME springs are linear rate, so if you know the unsprung weights of the Jeep, the free length of the spring, and the spring rate, a simple formula can get you pretty close to the lift height you are aiming for without as much guess work. Progressive rate, or dual rate springs (JKS JSPEC springs), are tougher to figure out, and also tougher to match a shock with.

https://offroadpowerproducts.com/blog/progressive-rate-coils-versus-linear-rate-coil-springs/
Debate can be had with that article, but it gives you the basic understanding between the 2 types of springs.

InOmaha said:

And if you download the application guide from ARB you get slightly different information, where they say most of the springs give a 2" lift.

https://arbusa.com/site/wp-content/uploads/jeepWranglerTJ.pdf

But I'd go with the above 2.5" if you're planning. Most of the springs and shocks in these 15 year old Jeeps are a little tired so you gain 2.5" from worn rather than 2" from new.

I think most people would have the best results with a 2933 front spring and an added spacer or not for looks. Then a 2941 rear spring for a regular TJ and 2949 rear spring for an LJ. Most everyone runs a winch so the heavier front spring seems more appropriate and the rear is different due to the added length and weight of the LJ (especially with a hard top).

TJ 2933/2941
LJ 2933/2949
Front spacer to taste

Nowhere on or in the box does it mention what to do with the A and B springs. I searched around the internet and ended up putting the A springs on the front driver's side and rear passenger side. B springs front passenger side and rear driver's side. The end result was perfectly level on all corners.

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Yeah, there are hundreds of springs to choose from. I used to comb through them and fool around with sprung weight and coil spring rates to sort out what would work best for my setup. I never found it confusing like some do. It was just plugging numbers into a formula. The only thing I don't like is that the 2933's only give 2". Mine are only netting 1.75", so most people are going to end up with some kind of spacer if they are interested in running 32's or 33's and leveling out for rake. I have a 1.5" spacer to get me to 3.25". There is a spring that would probably give closer to 3". I never took the plunge to give it a try, but the math worked out. I think it was the 2934. They are for a ZJ, but work for our TJ's. Higher spring rate and a little longer, but shouldn't ride harsh with the good shocks.

Here's the cut out from the ARB.pdf



Notice the soft top/hardtop designations. I think they under report the lift because a lot of people have extra sprung weight like winches, aftermarket bumpers, skid plates, rock guards, and larger spares so they don't want to promise more height. The amount of lift you get will depend on how worn your current suspension is and how much extra sprung weight you have bolted on.

I measured mine before and after and the 2933 springs up front added 2.5" with an aftermarket bumper and no winch. I purposefully added another 3/4" to get to 3.25" at the front to compensate for a yet to be installed winch. The heavier springs in back added 2.75" but I have a soft top not a hard top which may have dropped it 1/2 inch.

There are too many variables to guarantee 2" of lift. If you go with 2933 and 2941, I would expect 2.5" of lift with the stock front/rear bumpers and soft top. Less in front if you have a winch, less in back if you have a 35" spare.

I didn't use them, but people have said to call DPGoffroad and they'll walk you through it based on what you're trying to do and the end results you want. I just erred on the side of heavier duty more lift for added weight in the future.

It's also confusing that the description in the table mentions added weight and is not the spring rates. So when you look a the "loads" above they are the difference in weight between soft top and hard top, or if you put 0-90 lbs on the bumper or 90-180 lbs. The spring rates and lengths in the .pdf table listed in the thread previously show how the different springs use extra length or spring rate to compensate for these added weights. The 2932 and 2933 springs have the same spring rates but the 2933 spring is longer, so if you put 90 lbs on it, it will probably settle to the same height as the 2932 with no weight on it.

hahaha. My ProComp springs (1 part number only) along with a .75" spacer in front netted me 2" of level lift and that's with aftermarket bumpers, a winch and a hardtop. Life is easy

Chris said:

Any idea what the free heights of the ProComp springs are in comparison to OME?

I notice the spring rates on the ProComps are much more than even the OME heavy springs.

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Nope, I don't. I only know the end result. See pic above.

I went with OME specifically because I have an LJ. Which for anyone who has an LJ knows, a lot of stuff gets more complicated when you have an LJ. They have more weight in the back and need different springs to compensate (especially with a hard top), there are few off the shelf storage options, it's almost impossible to find a hard top unless you grab that one that's listed for months in a state 3 over for $2,500, the soft top and windows are harder to find and more expensive, there are less options for some armor and you pay more, etc., etc.

The one nice thing is I didn't get any vibrations with a ~3" lift and no SYE. I read enough stories of people taking their lifts back apart to add spacers, front or back to level out their LJs that I picked the springs and spacers I did to get the results I wanted the first time. I think with a different lift, I may have needed rear spacers to compensate for the added weight of the LJ rear end.

Chris said:

@wrangler4fun, there are some older threads from @jjvw where he gets into details about the different OME springs. I know he experimented a lot with different OME springs until he found something that worked (before switching to Currie springs).

I know that when you know your sprung and unsprung weight, it helps tremendously. However, if what you're after is 2" level, I'd probably get the medium duty fronts and light duty rears.

That is assuming you have a soft top, half doors, 31s, no heavy tire carrier (factory), and aftermarket bumpers and a winch.

I however would lean more towards medium or heavy rears, only because if you plan to carry anything in the rear (including people), the extra lift height in the rear will be nice to have so that when weight is added, it will compensate.

However, reading all this stuff, I honestly think the ProComp springs @CodaMan is using might be a better choice.

I believe his stance looks similar to my black Rubicon, which is IMHO a great look for a TJ.

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Mine on 2" ProComp springs, .75" spacers in front and a 1/2" body lift w/32's

Chris said:

@wrangler4fun, there are some older threads from @jjvw where he gets into details about the different OME springs. I know he experimented a lot with different OME springs until he found something that worked (before switching to Currie springs).

I know that when you know your sprung and unsprung weight, it helps tremendously. However, if what you're after is 2" level, I'd probably get the medium duty fronts and light duty rears.

That is assuming you have a soft top, half doors, 31s, no heavy tire carrier (factory), and aftermarket bumpers and a winch.

I however would lean more towards medium or heavy rears, only because if you plan to carry anything in the rear (including people), the extra lift height in the rear will be nice to have so that when weight is added, it will compensate.

However, reading all this stuff, I honestly think the ProComp springs @CodaMan is using might be a better choice.

I believe his stance looks similar to my black Rubicon, which is IMHO a great look for a TJ.

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The fact that I ended up with Currie 4" should tell anyone enough about the results of my experimenting.

The great thing about OME is that they have multiple options in the 1-3" lift range that will help set the front and rear ride heights. The frustrating thing about OME is that they have a whole bunch of options.

I read just enough to get comfortable with my selection, then stopped reading more. At some point you just learn too much useless information that doesn't apply to what you're doing.

If you stick to the 4 springs (probably the three) I listed in this thread they will likely work fine. The more crap you plan on hanging on your Jeep, the heavier duty the springs you should buy and since most everyone ends up with a winch that means the 2933 front springs. You'll probably get closer to 2.5" than 2" with 2933/2941 TJ, and 2933/2949 LJ combos. Then 3.5" with a body lift. Measure your individual Jeep's rake before and assume the springs you chose will have the same lift height front and back, then add spacers to level it to the amount of rake you want to be at in the end. You'll probably be close enough. Most of the stuff that would drag the rear down are hardtops and heavy bumpers with swingout carriers for 35" tires. If you have big tires you should have a bigger lift anyway.

The A/B spring tags were an annoying surprise I had to figure out when my Jeep was up in the air with no front springs on.

Chris said:

What are you considering 32s? 285s?

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265s, so 31.7". Probably 285s next.

Chris said:

The rear heavy springs are shorter than the rear light springs. Is that correct?

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Yep.

I believe OME tried to design their spring lineup for about the same lift height over a variety of possible applications. Through spring rate and/or unsprung length changes to compensate for heavier rigs. And then all kinds of variations just to give people options.

But they should probably spend some time writing up a brochure or something that explains it all in a straight forward manner.