hdrider

Very informative,, nice write up.... So my question is.... between my 2.5" OME lift and a 1.75" coil spacer I'm at 4" of lift. My rear axle is at a pretty steep angle... front for some reason does not look to bad.
So could I get away with replacing upper control arms in the rear and still run my stock drive shaft?

wal0vitch

Im going with the rustys 3.25 in lift and I was going to go with front and rear lower control arms.. My question is do I need to go with bolth. And is that all I would need for control arms. I have a 4 door.

Thanks this is a grate thread I was having problems with this concept..
~Adam~

w squared

If you actually end up with 3.25 inches of list (I'm not familiar with Rusty's), then you probably don't need any rear control arms.

Front lowers are not truly needed...but they're a good idea with that amount of lift. I think you'll be much happier with your Jeep if you get front lowers (or some Currie front uppers).

wal0vitch

from what im told i net 3.8in lift...

w squared

Okay...if you're going to be getting that much lift, I would suggest front lowers (or Currie front uppers because they can have the same effect and they're GREAT arms). Even though you have a 4-door, I would also consider rear uppers - it might extend the life of you rear drive shaft.

Does anyone that netted 4 inches of lift on a 4 door want to chime in here?

JPop

Plenty of good information here, not sure how I missed it first time through.

One thing that hasn't been mentioned is how control arms effect instant center, dive and squat. If I were to draw a line that matches the angle of the rear upper and lower control arms where the two intersect become my instant center of gravity. Add a lift and the point of intersection and instant center becomes higher, in round numbers 3 inches of lift will add 5 inches in height to the instant center on the JK with stock arms.

The same thing holds true for the front suspension although IC is primarily a concern in braking with the nose diving.

Anyway, I don't want to go into too much detail as it's beyond the problems that most people want to solve. Also, my experience with suspension geometry come primarily from drag racing although the physics really don't change wherever you may roll.

barrett_fodder

planman - best summary and explanation of how the control arms factory into a suspension lift that i have seen on these forums. I had to literally read dozens of posts and take 'notes' to get the same info. Thanks a ton!

style_front

so 2 to 3 inches and all I really need to make it drive stock again is front adjustable arms, upper or lower as long as I can adjust caster. This is the thread I needed to read, I am about to pull the trigger on a small lift right now, if only I could figure out spring rates I'd know exactly what I needed.

spinlock

You the CAs to align your JK, hopefully it drive better than stock.

The adjustable LCAs will give you a larger Caster adjustment range just by nature of the location.

style_front

With the addition of shocks and adjustable arms up front it sounds like I would be squared away to do some good rocking with either one of those setups. Atleast, according to what Ive learned in this thread here. The krawler with 3.5 might be pushing the limits of the pinion angle though, some one correct me if I'm wrong..