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Beginners guide to lifting your JK

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This is just to help with your lift setup. Some basic questions I see asked a lot on the forum ie. alignment, do I need XX, etc. Ill gladly go over and help choose a kit for your Jk. I am in not a suspension expert but know my way around. If something here is not covered ... Please ask. If I can't answer the question. I will do my best to find the answer for you. Don't be afraid to post here. the question/answer can help somebody in the future. GOOD LUCK !!!!!!

Tourque your boltsTourque specs for the jk can be found HEREon Project JK.

Death wobble: it's very important to properly torque your suspension bolts with the jeeps weight fully on the axles/tires. Not doing so can have the bushings in a bind and lead to problems.
ORE's explanation here
Death wobble is extreme. The front axle wanting to rip from the jeep, only stopped by coming to a complete stop. if not fixed can continue to reek havoc on your front end. The front axle is constrained by your upper and lower CA's and track bar. Usually a loose or bad Ca/bushing is not enough to for DW, any other lose or worn component for that matter. Add a bad track bar/track bar bushing or worn mount hole-all bets are off. Please see PlanMan's thread here on DW. Also the sticky on the grade 8 bolt upgrade. DW is serious and can cause a train reaction of broken parts if not fixed. Remember to always fully check torque periodically. Mark your bolts using a paint marker for a visual

Flighty/loose steering: If the jeep is lifted without caster correction, you might feel the steering to be flighty. The reason, adding lift height lowers caster. positive caster helps the steering wheels return to center. The stock Jk has around 4* caster and light compared to other vehicles. At 3" if height, you will likely want to adjust for more caster. Some of the cheaper lifts are for a reason. No caster correction is one of them.
Some fixes for caster angle
cam bolts (I do not recommend) Control arm drop brackets (AEV/Rancho/RC) Fixed length control arms Adjustable control arms Cut and rotating the C's or a aftermarket housing like Prorock or TF I just learned of folks using off set ball joints for caster. It's all new to me so I can't help you here Some info on caster here

Steering wheel not center You will need to adjust your steering wheel back to center using the drag link. If you have a Procal it can assist in doing so.
Toe Should be no change but ideally you want total 1/8 to 1/16 in.
DIY toe check
Camber If camber is out of spec you have bigger problems. Bent axle tube and/or C or possible balljoint issue.
Caster see above. Stock 4.2*

"Do I need control arms? "You have 8 control arms that are not adjustable. Adjustable CA's correct axle angles (pinion/caster and wheel base) Adding height the axles rotates up and in towards center.
Aftermarket control arms typically have better joints for less bind and clearanced for bigger tires. Longer control arms will also help the axle not steer itself as the axle articulates. If you look at any pic with a jeep flexing w/ stock CA's. The drooped side will pull in towards the pitch seem.
If lifted say 4", ideally you would benefit with all 8 arms to center the tires in the wells, pinion angle and caster angle.
"Do I need all 8 control arms?" No ... On a budget... Front lowers are commonly used for caster (adj'd longer then stock). Front uppers can be used as well (adj'd shorter then stock). Next I would add rear uppers for pinion angle (especially with a 2 door shorter rear DS)
Another option fixed CA's. One idea is to use fixed lowers and adjustable uppers. Great option and will save some $$$

one big misconception, after market control short/mid arms gain flex or articulation. This is not true. Flex joints/spherical joints/Heims used in aftermarket arms allow increased misalignment. This lets the axles flex easier/bind less.. Not add travel. Travel is ultimately your shock lengths

Rock Krawler mid arm

Teraflex fixed arm

long arms or short arms?
Long arm kits do not add articulation or flex. Long arms correct geometry and reduce operating angle running higher lifts. Issue being ... Unless its a custom install ...You're at the mercy of the manufacturer. Do your homework before choosing a long arm kit.
A good rule of thumb. Unless lifted over 4" of lift, running 12" travel shocks or coil overs, and 40" tires. You do not need a long arm kit.

steering wheel jerks left/right over bumps: This is known as bumpsteer. Bumpsteer is caused when the track bar and drag link angles are too steep, lengths, and geometry are off. As you go over a bump with one tire, the jeep jerks and sometimes will steer itself. Bumpy roads can be scary with a good case of bumpsteer. Bumpsteer is really is not a issue until up around 4", but the fix is a steering correction kit Raising the track bar & flipping the drag link is the ideal way to fix bumpsteer at higher lift heights -returning the geometry back to normal. Some kits do this similar using a drop pitman arm. I do not recommend using a DPA, it actually puts more stress the steering box. lowering the track bar reduces front roll center. one of the other benefits of a raised TB bracket is roll center correction.
SteerSmarts Extreme duty flipped drag link w/ Artec weld on raised TB bracket

Roll center/trackbar brackets adding lift height lowers the jeeps roll center. this can cause poor corner handling/steering. Raising the track bars at their mounting points will return the roll center to stock or higher. also keep the axle better centered during articulation.
oversteer/understeer Raising the rear track bar alone (front remains stock)= A positive roll axis/understeer. a little understeer is a good thing.
Raising the front trackbar alone (rear remains stock)=a negative roll axis/over steer. oversteer can cause handling to be unpredictable. you definitely don't want this.
Most kits in the 2.5+ range will address the rear. Notes:
- A shorter wheel base 2 door, oversteer/understeer will be more pronounced.
- The front track bar can not be raised without flipping the drag link or running a drop pitman arm (see steering correction kit)
- track bar drop brackets only purpose is axle positioning or axle center. usually supplied in cheaper kits.
Teraflex Raised track bar bracket

Axles off center laterally: Adding suspension height will shift the axles. Front to the driver side and rear to the passenger side. A adjustable track bar is used to recenter the axle.
I usually recommend the front first. this will add a little rigidity to the front end and firm up the steering. A 2.5' lift will shift the axles maybe 3/8", not enough to be a concern in itself imo.
A rear 'axle side' track bar bracket will center the axle up to around 3" of height. raising the rear track bar will also improve roll handling.

Axles not center in wheel well (wheelbase) to return wheelbase back to stock - or better. All 8 adjustable control arms are needed. Lowers push the axles for/aft, uppers set pinion and caster angles.
Added on 5/9/16 This is a cool pic from Dirtman that shows how much wheelbase is lost w/ a 4 lift and factory CA's. The wheelbase does not change as much as one would expect .345x2 or .690 total both axles. Just proves you really dont need all 8 CA's under 3.5" of lift. Front lowers for caster and rear uppers for pinion on a 2 door.

When do you need driveshaft's? Adding lift height steepens the angles the driveshaft's operate at. Adding longer shocks will allow the axles to droop further. Disconnecting the swaybar links-even more. If the driveshaft doesn't contact the exhaust/crossover pipe the cv will eventually fail.
Some of the Fixes-Exhaust spacers/y-pipes/limit straps or a smaller ID driveshaft. There is no magic number that says you will or will not have issues at xx height, too many variables. So just make a habit of crawling underneath and looking for split boots and spitting grease. When you do decide to swap out driveshafts, adjustable arms are now very important to set proper pinion angles. **note** In some cases, running a taller lift and aftermarket Drive shaft, some will have to give up caster for pinion angle to prevent vibes, or worst case-the TC damage. Best bet here is a aftermarket housing with 10* separation. Or like mentioned ... Cut and turn the C's

Swaybar end links: most smaller lifts sold, only include longer rears. The stock rears are used in the front. The swaybar itself should be parallel to the ground at ride height +/- a few degrees. If running a longer shock you run the risk of inverting the links and causing damage. Plus drivability will suffer not extending the links. Quick disconnects are obviously another option.

shock lengths: Shock length is your axles downward limiting factor. adding height reduces downtravel running stock length shocks. The stock Rubicon shocks are around 8"in travel iirc. Shock extensions are a inexpensive way to add travel. they work but limit uptravel if the jeep is set up to utilize all of it [travel]. Most shocks list lift ranges ex. 0-2,4-6 etc. but you'll want to choose what works best with your setup.

Bumpstop height: every jeep is set up different. Choose your tires and shock size. Then decide on bumpstop size. Extended bumpstops limit uptravel . this protects the shocks, keeps tires from rubbing the flares, etc.
If running a drag link flip, the drag link away from the frame at full stuff. Theres other possible interferences depending on different components, so its important to cycle the suspension [full bump and droop] to determine BS lengths.
Take a look at this picture.
You can see i removed the yellow stop and fully compressed the axle. Look at how much shock shaft is showing (1"), or 1" wasted up travel. The idea is to maximize up and down travel utilizing every bit of shock travel.
I could do 2 things to reduce the amount of shaft showing.
1/ decrease stop 3/4 as long as no other parts contact each other.
2/ raise the lower shock mounts 1/2
So i decided to lesson the amount of bumpstop. First making sure nothing else got in the way for example drag link and frame.
The Rancho front shock can collapse 100%
Leaving .5 shaft left showing at full compression.

Important note on lift height:
The general consensus is 2.5" is "safe" and you don't necessarily need CA's/TB's and all that good stuff. Yes this is true BUT. Aftermarket coils are designed not to sag under heavy weight. Some note that (listed heights are with a fully outfitted jeep). W/O bumpers, a winch, tire carrier, armor etc, it's not uncommon for a 2.5" lift to give you 1" or more in height.

general tire/lift height guide
** Backspace 4.5 or less
33's 0/1.5/2.5
35's 1.5 w/ flats/2.5
37's 2.5 w/ flats /3.5
40's 3.5 w/ flats/4.5

My goal here was to keep this simple. If anybody has any questions, please ask and I will do my best to help. others, don't be afraid to chime in. this discussion is for all.

Edit 11/1/2015

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Very good info for me. I am not looking at anything more than 2.5" but I have a 2 dr J/K and have even heard horror stories about a small lift. Thanks again.
2.5 is generally a safe height to be at. The issue is, most lift coils are stiffer and made to support weight. So if you don't have heavy bumpers/winch/tire carrier/skid system/etc. that 2.5" lift might end up at 4" :whistling:
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I have heard of people welding add'l pieces of spring onto their spring in order to lift it, but this was my mechanic friend who lives way out in the sticks where nobody has any money. That is why I thought it might work the other way by cutting some off, but I wouldn't do it to anything that I cared much about how it would ride.
:eek: :eek:
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I have a 2dr and just purchased 4dr springs, much higher rate then what I have now. I was debating of doing a BB ontop of them. Definitely on a tight budget but want some clearance.any issues with this?
A friend out 18's on the front of his Jk and a RC 2.5 BB. Complained of jittery steering and installed AEV's drop brackets.
You may or may not have a caster issue depending on the height.

What about trimming the factory flares ?
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Control arms locate the axles in the wells along with set caster and pinion angles. Good there !!
Driveshafts if not soon ... Later. Just keep an eye on them. The Cv joint will split and shoot grease as a warning, I replaced my front but still running the stock rear on a 2 door w/ 3.5" lift.
In your case less is better IMO. A JK can fit a 33" tire without a lift. The wheels (size does not matter) should have 4.5 or less back spacing.
You can opt for a small leveling kit that will remove the factory rake and lift the rear a bit. Or a 2.5" BB. Both will get you a little more clearance and not affect geometry or the ride much.
I'm thinking I might be in this boat. I just installed a 2.5" TF lift on my 2 door and when I got my front end aligned my caster came back as a 3. :jawdrop: I was a little surprised it was this low with just a 2.5" lift and that fact that my Jeep still handles fairly well.
^ I was running 3 caster and the jeep drive like ass. No two jeeps are the same. How are your roads ? Roads around here are garbage. Even the highway is rough going.
That would make a difference as well.
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I never had my numbers on the last jeep but I'm sure it was off too. It drove fine after the 2.5 for about a year or so but I wheeled it and smacked on some 35s and that's when problems started showing up with steering. Hard to say which got er there.
That's right, you grabbed some Synergy stuff. Tie rod and drag link.
Hi there, I was just wondering... is reprogramming using a procal or similar device necessary when adding 2.5" lift and 35" tires for the Jeep to be able to run correctly? (manual tranny, and I understand speedo and tpms would be out, but is there anything computer-wise that would prevent me from traveling to a shop to have the programming done?) Do most guys buy a procal or have a shop do the reprogramming? Is a procal something that would be used more than on one occasion if there were no other suspension/driveline/tire size changes? Thank you
Procal is to set for tire diameter am speedo/odo plus some other things. A dealership can do THE Spe/odo but it will cost you. Yes you can keep using it but I believe it can only be used on one jeep at a time.
The roads here are pretty good. I did have a worn ball joint for a while and my steering was a little loose at that point, but once it was replaced, my front end aligned and toe set my steering is pretty tight again. One thing I have noticed is a little steering wheel wiggle between 45-55 mph, but I believe that is due to tire balancing and I'm planning on heading back into Discount Tire this week and have them rebalance my tires. I'm running GY Duratracs and I've heard they can sometimes be a pain to balance properly. I've considered adding a set of geometry correction brackets. Now that you've tried both the AEV and Rancho geo brackets which do you prefer? How much more caster do you believe each would give me? I wouldn't want to add so much more caster that I start having drive line vibrations as I'm still running the stock front driveshaft. Thanks.
Exact lift amount total and front ?


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The total lift is supposed to be 2.5". So I would expect 3" in the front and 2" in the back (to adjust for the factor rake). From the top of the spring perch flat edge to the edge of the spring tower back side I get 11-7/8" From the center of the shock bolt to the bottom side of the shock tower where rubber bushing touches I get 21" That is exactly 2.5" difference for both from the stock jeep illustration figures of 9-3/8" and 18-1/2". So it would appear I only have 2.5" of lift in the front. Do you have a similar illustration for measurements in the rear?
No because that diagram is for use installing the brackets.
201/4 front and 211/4 rear from mid wheel to bottom flare I confirmed to be good stock measurements as well.
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Google "AEV correction brackets" on the AEV site there's a PDF for the instructions which shows the diagram.

There's 3 holes on AEV's brackets. The 2.5 hole is set to give a little caster bump. The 4.5 (top) hole is set to not allow as much rotation for caster. Caster should remain the same for 2.5 - 3.5 and 4.5 being the holes are not set in the same locations. I believe AEV targets 4.5 or so.

The Rancho brackets only have one hole. Iirc is the same as AEV's middle 3,5
Not having the other 2 holes the caster will change at different lift heights.

Rancho can correct me if in wrong, but I believe (like stock) as you lift caster decreases. So... At 2.5 you will have more caster then somebody at 3.5 (me -4* ish)

Not a bad thing because the higher you go caster can actually hurt you. 6* at 2.5 is high but ok. At 3.5" the driveshaft angle would be pushing its limits.
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I'm new to the jeep world. I don't do any off roading. I just want the off road look on a 3000 budget. I purchased 18 in rockstar rims. Not sure on tire size or brand. And if I will need a lift. Please help
Including tires ? $3000 is a good chunk of change. Not a bad thing but a lot to spend for look over function. Is the 3k just for a lift, what size tire and how high you want to go?
Fwiw .. A 35" tire will fit comfortably under 2.5"
A 33" will fit with no lift at all.
Thanks for all the details. I'm guessing I would use the 2.5" hole on the AEV bracket and that would hopefully bring me back up to around 4 something degrees of caster. I actually like the design of the Rancho brackets better, but am afraid they may be too much for my 2.5" of lift. How long will it take me to install the AEV brackets by myself? Just read the instructions and they said to work on one side at a time. Did you have to pry your exhaust out of the way to install them? That sounds like a pain.
Use a Sawsall. We didn't have one and used a hand saw. I was unable to pry it. 2 people it took longer. The other person sometimes can Just get in the way. Me personally, I am more focused by myself.

switching over to the Rancho brackets took me less then a hour to install.
I was doing some reading and saw a reference to a 2" front lift for a 4 dr jk and with the 0 rims they could fit 34" tires and level the ride for a weekend warrior like my self . no big mud or rock climbing.. Please help :awesome:
Why not go with a 33" w/ no lift ? OR.... i think what you saw was a leveling kit using spacers. Usually 2" front and 1" rear. Enough to level the jeep and provide a small lift.

Assuming 0 offset ? You want a wheel regardless of diameter to have 4.5 or less back spacing.
Yes coils are rated for weight. TF offers a 2 and 4 door coil which will put you closer to advertised height. RK does not .. So a 2 door averages about 1" more. Regardless a light weight stock jeep will be higher.

Most kits remove the factory rake and that's the reason for more height up front.

33's will work as long as the wheels have 4.5 backspacing or less. Will it rub heavily flexed ? Most likely yes. A small leveling kit will help.
Another option is flat or trimmed factory flares.
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