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-   -   Newby's guide to lifting your JK (http://www.wranglerforum.com/f202/newbys-guide-to-lifting-your-jk-298665.html)

kjeeper10 09-17-2013 08:01 PM

Newby's guide to lifting your JK
 
This is just to help with your lift. 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 HERE

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. 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


Alignment:
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. Bigger tires you might need to increase toe from what it was factory.
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 axle rotates up and towards center.
Aftermarket control arms typically have better joints for less bind and clearance 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. Long arms fix this totally but short arms will help a bit.
Ideally you want all 8, for pinion angles/caster and wheel base.

"Do you need all 8" No ... On a budget, Front lowers are commonly used for caster (adj'd longer then stock). The 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 is fixed CA's. For a quick fix ... Go for it. I don't recommend if you have any desire to upgrade in the future. A lot of times, folks will install drop brackets for the front caster angle, and rear uppers for pinion angle. Next rear lowers to correct wheelbase.

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 steers itself. Bumpy roads can be scary with a good case of bumpsteer. this 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.

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.


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.


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.

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.

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.

Ken

StarBrite 09-17-2013 08:29 PM

Thanks, Ken! Your tutorials ALWAYS teach me something new!

I appreciate the time you spend creating all the write ups you do for the benefit of the forum!

:Thanx:

tabber02 09-17-2013 08:37 PM

well said Ken :thumb: this is going to help a lot of members out!

Captain Ed 09-17-2013 08:44 PM

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.

kjeeper10 09-17-2013 09:21 PM

Quote:

Originally Posted by Captain Ed (Post 4657577)
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:

Callmebyars 09-17-2013 10:23 PM

Wow very informative. Me and my buddy are putting on my 3"lift this weekend. Now I see I'm probably going to have to spend more money on more parts.

kjeeper10 09-17-2013 10:53 PM

Quote:

Originally Posted by Callmebyars (Post 4660713)
Wow very informative. Me and my buddy are putting on my 3"lift this weekend. Now I see I'm probably going to have to spend more money on more parts.

Good luck. Did you end up getting the TF 3" ?

Callmebyars 09-17-2013 11:32 PM

Yup is getting a3" taraflex lift with 35" toyo m/t. Also planning on getting my flat Fender flares on and if there's times both bumpers

dawhitesJKU 09-18-2013 01:41 AM

Great write up for newbie edjumacation.

Daniel_M 09-18-2013 12:43 PM

Agreed. Newbies need to read it that are thinking of lifting. Especially ones that post "I am thinking of this 4" lift for $400".

Make it a sticky?

-Dan

Rough Country 09-18-2013 01:32 PM

Very good info for people to know!!! This will be something I share with new people I come across. Thanks!

jeepRN81 09-22-2013 08:56 PM

So, for a newbie like me, who is also thinking about a lift that won't break my pocket... what do you recommend?

JeepRN81

kjeeper10 09-22-2013 09:15 PM

Quote:

Originally Posted by jeepRN81 (Post 4779257)
So, for a newbie like me, who is also thinking about a lift that won't break my pocket... what do you recommend? JeepRN81

God there's so many choices. Sticking with a small BB you can avoid the headaches if on a budget.
$200-$300

Stosh1 09-22-2013 09:41 PM

Quote:

Originally Posted by kjeeper10 (Post 4658937)
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:

Can you just cut some off the ends of the springs until you get the height you like best?

kjeeper10 09-22-2013 10:12 PM

Quote:

Originally Posted by Stosh1 (Post 4780505)
Can you just cut some off the ends of the springs until you get the height you like best?

Never heard of anybody doing this. Don't think it would be something easily done anyways.

tabber02 09-23-2013 09:18 AM

Quote:

Originally Posted by kjeeper10 (Post 4781385)
Never heard of anybody doing this. Don't think it would be something easily done anyways.

^^ not sure i would screw with that.. a lot of engineering goes into those springs, rates, height... and just because you remove an inch... i doubt that'd directly translate to an inch of lift.

better course of action would be to do a lot of research, talk with some objective people... and decide on the springs that will get you close to your desired lift height. .one word of caution... while franken-lifts are fun (i have one) - you may wind up spending more to get things to ride the way you want...

:mooning:

Stosh1 09-23-2013 10:18 AM

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.

kjeeper10 09-23-2013 10:25 AM

Quote:

Originally Posted by Stosh1 (Post 4790641)
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:

Jkchris2dr. 09-23-2013 10:30 AM

Quote:

Originally Posted by kjeeper10 (Post 4779873)

God there's so many choices. Sticking with a small BB you can avoid the headaches if on a budget.
$200-$300

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?

kjeeper10 09-23-2013 10:42 AM

Quote:

Originally Posted by Jkchris2dr. (Post 4790897)
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 ?

MotorCityJK 09-23-2013 11:01 AM

Quote:

Originally Posted by kjeeper10 (Post 4781385)
Never heard of anybody doing this. Don't think it would be something easily done anyways.

Cutting springs is fairly common in the car-world (used to drag race 5.0/4.6L Mustangs). Cut-off wheel makes quick work of them (torch is a big no-no). But those are vehicles that don't see the spring cycle out to full droop. Not sure if you'd risk the spring dislocating or not on the JK.

Trick was you started off cutting a little as, correctly stated, cutting an inch of height off the spring doesn't necessarily translate to an inch of ride height.

Jkchris2dr. 09-23-2013 11:07 AM

Quote:

Originally Posted by kjeeper10 (Post 4791137)

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 ?

*ground clearance.

Callmebyars 09-23-2013 12:52 PM

So since I'm finally doing my 3" teraflex lift w/ 8 flex arms and 35" ties looks like I should invest in an adjustable control arms and maybe a new drive shaft. Anything else I should look into? We're putting it on a 13 jk sport 2 door. Also I remember reading on here somewhere that when you lift ajeep that your tires move closer together due to the lift. Will an aftermarket driveshaft solve that problem or do you have to relocate the axles?

tabber02 09-23-2013 01:09 PM

Quote:

Originally Posted by Callmebyars (Post 4793809)
So since I'm finally doing my 3" teraflex lift w/ 8 flex arms and 35" ties looks like I should invest in an adjustable control arms and maybe a new drive shaft. Anything else I should look into? We're putting it on a 13 jk sport 2 door. Also I remember reading on here somewhere that when you lift ajeep that your tires move closer together due to the lift. Will an aftermarket driveshaft solve that problem or do you have to relocate the axles?

the flex arms you reference are adjustable (so no need for the second set of adjustable arms)... not a bad idea to look into driveshaft(s) though...:beerme:

kjeeper10 09-23-2013 01:56 PM

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.

kyanez76 09-24-2013 11:53 AM

Thanks for all that info but me being a newbie looking just to make my ride look a little intimidating, I could use some guidance. I have a 2011 4dr JK i just bought. Everything is stock so far and I want to lift it and add larger tires, possibly change the stock 17" rims. I want it to be drivable in town but still look good. What do you recommend for rim size, wheel size, and lift? All the help is appreciated. I cant pour tons of money into this thing and want to get it right.

kjeeper10 09-24-2013 12:20 PM

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.

GreenRubi 09-24-2013 04:36 PM

Quote:

Originally Posted by kjeeper10 (Post 4658937)
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:

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.

kjeeper10 09-24-2013 04:52 PM

Quote:

Originally Posted by GreenRubi (Post 4825729)
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.

ESP 09-24-2013 06:46 PM

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.


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