Many folks are talking about adjustable control arms with their lifts, but which? For a 3" or so do we need all eight or can we get by with just the uppers? Lowers? Lots to learn around here.

Stay tuned for the next question, what do we do with them once we get them?

 

Here is TeraFlex's view on replacing the arms.

http://www.teraflex.biz/installsheet...ms_install.pdf

 

Given that information and my opinion that Teraflex has the best "overall" lift there is, I would listen to what they have to say.

 

I'm interested also......

 

X2 on that

 

So according to TF front lower and rear upper will get us by. The caster should be set at 4.5 degrees and you can do this by lengthening the arms to set lengths. Is there a poor man's method for measuring the caster so it can be dialed in for our specific vehicles? Also, does this automatically set our pinion angle correctly for new drive shafts?
BTW, thanks Mini-me for the link.

 

I'm not an expert, so I'll most likely miss something here. This is how I understand the answer.


for the Front Axle:

Upper control arms are best at adjusting Castor

Lower control arms are best at adjusting axle position/wheel base

If you want to fine tune your street handling and feel, you'll need upper control arms (I'm not going to go into caster bolts here).

If you are running very large tires - you will most likely need to adjust the axle position, in order to properly place the tire inside the wheel well to avoid rubbing at full flex. I would guess that if you are having to move your axle position that you'll also need to adjust castor.

So on the front, you may need upper adjustable control arms but not lowers. But if you need lowers, you'll most likely need uppers also.


for the Rear Axle (I know a lot less about the rear, so I'm guessing here)

Upper control arms are best at adjusting driveline angle (alignment of the rear drive shaft to the differential pinion).

Lower control arms are best at adjusting axle position/wheel base

Now if an expert to come along and clean this up, you'll hopefully have some good information.

 

Sadly the pdf only showed some measurements plus a variable, but nothing that enhances the understanding of.....why? Especially when they bring up an issue of the Jeep pulling to the right. What's up with that? Is that due to the track bars offset when lifted?

I just went out to my driveway and took a look at the differentials. Front is a D30 high pinion, which would make it easier on a lift to correct. The rear has a D44 low pinion. :( When you lift this the angle can become extreme depending on amount raised.

Now it the rear were changed out to a high pinion at the time of the lift then most likely all the radical problems associated with rear drive shafts would vanish away.

Adjustable bars drawbacks could be that they get knocked out of their original settings? I don't know.

To me it would seem that the original WB and track centers from factory could be retained through the judicious use of adjustable track and control arms. Has anyone seen any aftermarket manufacturers address this issue and give us "perfect" high lift kits?