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So I ordered a pair of Superlift 4" coils for the front, RE adjustable track bar and shocks for my MJ. I am doing a SOA in the rear using 2wd leafs. Tires are 32 x 11.5 R15. Am I going to have issues with control arms and pitman arm at this height that need to be addressed as well? What other advise can you guys give me? I am used to Jeeps with leafs.

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Doing SOA in the rear with 2WD leafs will probably net you 5" of lift depending on the condition of your leaf packs.

 

Drop pitman arms should ONLY be used if you're lowering the trackbar mount on the frame, or raising it on the axle, otherwise it will cause bumpsteer. The whole belief that you need a drop pitman arm with a lift has been perpetuated from the days of leaf sprung vehicles without trackbars. On these vehicles you wanted to keep the angle of the draglink as flat as possible to minimize bumpsteer. On vehicles with a trackbar (like on your MJ), you want to keep the draglink as parallel to the trackbar as possible to minimize bumpsteer. A dropped pitman arm will also increase the amount of torque/axial loading on the shaft your steering box experiences.

 

With 4" of lift your ower control arms should be at 16 3/8" and your upper control arms at 15". You can get away with using your factory uppers but the lowers really should be about an inch longer.

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  • 2 weeks later...

So I have been doing some reading on some other threads, and I am not sure if I want to go thru with SOA with 4" front. I do have some 2" spacers I could add to the front which may level it out, but I don't want to go that high either cuz I am only running 32s. :???:

 

Looks like I may have to order some leafs for the rear to get what I want, just not crazy about spending more money.

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Started the SOA swap this evening. Coils should be in Saturday. I have to replumb the rear brakes as well as they were brittle and broke. My predicament is whether to swap in the 8.8 at this point. It needs lines plumbed as well, but I don't know the condition of it and don't have time to get into it before next weekend. I wasn't going to put it in yet as I know the condition of the Turdyfive.

 

I know I have to lengthen the rear brake line. Do I have to lengthen the fronts as well or are they fine?

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I know I have to lengthen the rear brake line. Do I have to lengthen the fronts as well or are they fine?

Lengthen.

 

I think I used '95 YJ front hoses. You need to rebend the caliber end metal tube slightly.

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With the fronts at 4" of lift you can just under the bracket that holds them on the inner fenderwell and bend the hard line straight and move the bracket about 4" towards the coil. Their is actually a hole already drilled there that the screw will fit in. Take about 2 mins per side and you gain the needed extra length.

 

Anything over 3.5-4" of lift you'll need longer front lines.

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Started the SOA swap this evening. Coils should be in Saturday. I have to replumb the rear brakes as well as they were brittle and broke. My predicament is whether to swap in the 8.8 at this point. It needs lines plumbed as well, but I don't know the condition of it and don't have time to get into it before next weekend. I wasn't going to put it in yet as I know the condition of the Turdyfive.

 

I know I have to lengthen the rear brake line. Do I have to lengthen the fronts as well or are they fine?

 

If you already have the 8.8, I'm not sure why you're considering using the D35. You are already going to need to add spring perches to either axle. Sounds like the perfect time to install the 8.8. :???:

 

Willy

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Started the SOA swap this evening. Coils should be in Saturday. I have to replumb the rear brakes as well as they were brittle and broke. My predicament is whether to swap in the 8.8 at this point. It needs lines plumbed as well, but I don't know the condition of it and don't have time to get into it before next weekend. I wasn't going to put it in yet as I know the condition of the Turdyfive.

 

I know I have to lengthen the rear brake line. Do I have to lengthen the fronts as well or are they fine?

 

If you already have the 8.8, I'm not sure why you're considering using the D35. You are already going to need to add spring perches to either axle. Sounds like the perfect time to install the 8.8. :???:

 

Willy

 

Unless he has those nifty swap pads that work with the under axle perches.

 

But X2 on doing the 8.8 swap now being you have to tear everything apart now anyways.

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I don't know if I have time to tear into the 8.8 before next weekend. Maybe I will leave the rear until last and base which one goes in then.

 

What do you need to do to it besides spring perches? Do you need to install gears or a locker?

 

Willy

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With the rear SOA and the front 4" coils in and the new tires, I ended up with 8"+/- in the rear and 5" in the front. Measuring from the floor to the flares, the rear is 4" taller than the front. Looks as if I am going to be ordering new leafs and going SUA as I don't want to lift the front that much to match. I am also trying to decide if I am going to order some new LCAs or build a long arm kit instead.

 

I didn't get the amount of lift in the front as anticipated. Is that because the springs may be rated @ 4" on a TJ and you won't get the same amount on an MJ?

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With the rear SOA and the front 4" coils in and the new tires, I ended up with 8"+/- in the rear and 5" in the front. Measuring from the floor to the flares, the rear is 4" taller than the front. Looks as if I am going to be ordering new leafs and going SUA as I don't want to lift the front that much to match. I am also trying to decide if I am going to order some new LCAs or build a long arm kit instead.

 

I didn't get the amount of lift in the front as anticipated. Is that because the springs may be rated @ 4" on a TJ and you won't get the same amount on an MJ?

That's not how lift is measured. Tires are a variable, because bigger tires change the ride height even without any lift, and conversely, you can add a lift without changing tire size.

 

If you still have the factory flares (in the original locations), the accepted way to measure lift is from the center of the wheel/hub/axle stright up to the underside of the flare lip. For XJs and MJs, the stock front measurement should be 17-1/2" (plus or minus not more than 1/2"). For the rear, stock XJs w/o the Up Country suspension should be 17" and stock MJs should be about 21"

 

And as to the front springs, TJ springs do not produce as much lift in XJs and MJs as they do in TJs. So if the springs you bought were tated at 4" for a TJ, you probably got about an inch or maybe 2" of actual lift out of them, and the rest is tire size rather than "lift."

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That's not how lift is measured. Tires are a variable, because bigger tires change the ride height even without any lift, and conversely, you can add a lift without changing tire size.

 

That's a no brainer. I do know how to work a tape measure. I was basically stating the differences between the front and rear. I theoretically should have netted 5" in the rear and 4" in the front. The new tires have a 1.5"bigger radius than the old ones, so if you subtract that from overall lift gained will give what I gained in just suspension. Regardless of whether one measures from the floor or from the axle CL you would come up with the same result.

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If it's a no-brainer, take out the tape and measure it the way everyone else does so we can all be on the same page. Trying to back into it by subtracting a theoretical tire radius, which is affected by tire pressure and given only as an "about" anyway, is not very accurate.

 

What you have said so far is that the back is taller than the front but you don't know by how much. How can anybody advise on possible corrections with that as a starting point?

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If it's a no-brainer, take out the tape and measure it the way everyone else does so we can all be on the same page. Trying to back into it by subtracting a theoretical tire radius, which is affected by tire pressure and given only as an "about" anyway, is not very accurate.

 

What you have said so far is that the back is taller than the front but you don't know by how much. How can anybody advise on possible corrections with that as a starting point?

 

I am not looking to get into an argument here. It doesn't matter how everybody else takes a measurment as long as your start and finish reference points are the same. I could have measured from the roof down and still got the same result. Simple addition and subtraction are pretty easy to do in my head. also, I did state that the rear was lifted approxiamately 3" more in my post, not just that it was higher. :wall:

 

Anyways, thats enough af that.

 

So I was just about to order new 4" leafs for the rear, but decided to try some 2" spacers for the front first. I am satisfied with the end result and am going to move forward with the SOA. Raising the front 2" dropped the rear by 1". If the 4wd shop that sold me the coils would have sold me XJ/MJ specific coils, I would have been further ahead, but they assured me that they would work.

 

I will try to get some pics tomorrow. image_209027.gif

I think it will look and perform killer.

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that looks to me like the rear is only about 1.5-2" taller not 4"? I can't see how you neted over 8" of lift in the rear just by doing a SOA. I got only 7.5 when i did mine and i have longer shackles too. I think your measuring the rear wrong...measure from the top of the axle tube to the inside edge of the framerail by the rear bumpstop and lemme know what that measurement is and i can help you figure out how much the front has to come up to match.. :cheers:

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