Just installed RK 2.5 mod suspension lift on my 2dr. and took it for an alignment. they corrected my toe in slightly and my camber is 2.2. It tracks straight and handles pretty decent. Will it hurt anything running the jeep with cater this low, other than handling characteristics? What i'm getting at is do I need adjustable LCA's to prevent any damage to suspension or drivetrain?

 

from what i know the caster keeps you straight it will not really affect tire wear or anything like that.

 

as far as pinion angle im not sure on the 2dr but i have a 2.5 and seems to be all good on my 4dr time will tell i guess.

 

Other than wasting money on that alignment, no, low caster won't hurt anything. You can always add the arms later if the flighty handling starts bugging you.

 

Caster at that low angle makes it drive very "twitchy" at highway speeds.
Mine was at 3 degrees after the lift and was a chore to drive on the highway.
I obtained 2 sets of take off lower control arms and used them to make a set 3/8" longer. That brought the caster to almost 6 degrees and made a world of difference in how the vehicle drives, both steering and amazingly ride quality.
Plan on posting pictures of how I modified the lower control arms soon .
So as a rule of thumb for every 1/8" you lengthen the LCA you gain a degree of caster.
The mod cost about a $100 to complete, that includes a 21MM socket and cutoff wheels for my chop saw.

 

I started with 2 sets of front lower control arms I got from board members.
Shipping only for one set other cost $40 shipped. Both sets were in excellent condition with low miles.
I used a carpenters finishing saw with a metal cut off blade to make the cuts on the control arms. (see attachments). I used a wood block 7/16" thick to set the cut length on one set and then removed the block for the second set. I cut the arms at a 30 degree angle to compensate for losses due to welding.
After the cuts were made I used the longer of the two ends to get a new arm length of 23". Stack length is 22 5/8". There was a loss of 1/16" due to blade thickness.
I spent $30 dollars to have them heli-arced at a local welder.



I cleaned the weld area's with a wire brush and degreased them, primed with an etching primer and painted flat black.
Total cost with a new 6 sided 21MM impact socket and two cutoff blades (available at hardware stores, Lowes and Home Depot) was right at $100.

 

Start your own thread in the Write-ups area. This has been asked about a few times, and will be easier to find there than on the tag end of someone elses thread.

 

Stock caster and steering angles are 4* caster with 2* of pinion angle (up).

When you move the caster to 6* you're changing your DS pinion angle to 0*. That won't work on a lifted vehicle and will cause driveline vibration and could cause a t-case failure.

This is why we designed new 'Unlimited' PR44 housing. Instead of 6* of separation on a stock housing, the Unlimited has 10*. This means you could have 6* of caster and 4* on pinion angle.

 

I agree if what you mean by 0° is relative to horizontal.

But....

Isn't pinion angle measured relative to the drive shaft, and not relative to horizontal?

 

If I understand your question.....

Pinion angle and DS angle can be vastly different. Pinion angle is relative to horizontal and not the DS. With a CV type DS you want the DS pointed nearly directly at trans or t-case yoke. With a standard DS you want the trans/t-case yoke within 2* of parallel of the pinion yoke. I'm not sure what the standards are for the funky JK DS.