Another rookie question. I need to adjust my caster because of the flightiness, so when making my control arms longer how do I push the axle forward enough to put a longer CA in? And caster should be anywhere between 4.5-5.5 correct? (4" and 35s).

 

So do I need front upper adjustable CA's to accomplish this?

 

You just need the lowers. put a floor jack under the pinion of the axle, remove the control arms and slightly lower the jack to install the longer arms. You want to have the weight of the jeep supported on jack stands before you do this.

 

Go up to the write-ups section, there is an index at the top, find the DIY alignment. It has steps and pics and a method to ballpark the caster setting.

 

I just talked to my local alignment shop and he claims if I to 5 degree caster it's gonna give me a hell of a shimmy, is that true?

 

No. A lot of guys run 5-6* without issues. Just watch your pinion angle and you will be fine.

http://project-jk.com/jeep-jk-tech/j...affect-my-jeep

 

Great article, just confused when he says 5* could cause possible transfer case damage and 1-2* is suggested.


Don't tread on me.

 

Caster and pinion are adjusted at the same time. When you raise caster to get better handling, you automatically lower the pinion, which makes the driveshaft joints work at steeper angles. Depending on the specifics, this may cause some vibrations, even if you can't 'feel' it.


The process might be similar to: buy bigger tires and install lift, re-gear to a higher numeric ratio to offset the tires (driveshaft spins much faster), replace stock driveshaft with a thinner aftermarket double cardan, adjust caster for better steering (lowering the pinion causing steeper joint angles), get up to freeway speeds, some type of driveshaft vibration resonance forms, transfer case explodes.

Haven't seen any lately, but there were several threads about this happening a few years back. Maybe people are more conscious of the angles these days?