Wheel Alignment Results - Caster And Other Questions

I went with Daystar because I believe USA made...I saw a fishbone bracket that was chinese and looked about as good as harbor freight stuff. I am trying to stay away from those kinda brands. Rather pay more for USA.

 

I think pretty much the same way. In this case, there's nothing wrong with the shackles I got, and when you compare them to the USA built stock shackles and bushings, there is no comparison.

BTW I wasn't familiar with Daystar brand so did a little research and don't see them advertising "Made in USA". Also, the company is Daystar International, so I have a hunch their shackles are made overseas. That's not always bad, I like stuff made in Taiwan generally speaking.

 

6 degree steel shims and new u-bolts added so it should come out to 7.2°. Test drive went very well but it is harder to steer when not moving. Moving down to 31" tires should help with that.

 

After an extensive test drive I have to say it's like a new Jeep. No wandering and no constant correcting the steering.

 

All this talk of shackle length, but I have no idea what is a Stock Shackle length?

 

I was wondering t same thing. I'm thinking 2-3/4" eye to eye. Hopefully someone can clarify it.

 

That looks like it could put more of a bind on your drive shaft?? I realize on the highway you won't be in 4wd and hopefully have unlocked hubs. I put shims in the opposite way years ago in a CJ7 front and back axles when I put a lift kit in. For u-joint life. I never noticed any change in steering... but I think they were only 2degree shims.
I learn something new every day!!

 

Had not thought of it that way, but makes perfect sense to me. As you said what is most important is that the center line of the axle pinion and the center line of the transfer case output shaft be parallel to each other. It does not matter if the these parallel lines are separated by several inches (within reason of course) just that are both parallel to each other. There fore lowering the transfer case at the rear could help match the needed parallel angle needed for a front drive shaft when you have installed caster shims to increase the caster on the front axel. Just another way of saying the same thing.
on edit: H Tate has a perfect diagram of the limits on this, thank you.

 

So this thread has me thinking about my Jeep's "twitchy" steering at speed. I crawled under it this morning and was surprised to see my front diffy pinion appears tipped upward. It's hard to tell about the t-case output yoke with the skid plate in the way, but just what I can see, it looks slightly upwards as well. Level at best, the worst possible scenario according to the diagram above. I'm thinking a wedge could be benefit me with the pinion angle and likely my steering also. I think I'll order some and take my jeep to the alignment shop. Thanks for and interesting and helpful thread.

H-tate Where did you source your steel shims?

 

WFO Concepts
I used the 6* 1.75" shims SKU: WFO 6.0-1.75
As FinoCJ stated, check your current caster angle to determine what degree you need. An alignment shop can get you an accurate reading.

 

Thanks ya'll.

If they're not terribly expensive I was thinking I might buy two or three sets. I'd like to have the shims with me when I go in to the shop so he can put them in with one trip.

 

You can get in the ballpark with an angle finder if you have a relatively flat surface to work on. Check the angle of your floor and then the angle of the knuckle to figure out what your current caster is. If I remember right (it has been a year or more), mine was pretty close to zero. Shims made a world of difference for me. I've been meaning to get it to an alignment shop just to know exactly where I am, but since it drives decent now I haven't really been all that worried about it.

 

I was researching alignment specs and it appears caster is one setting that is pretty forgiving. A whole bunch may cause your steering to be harder but that seems unlikely in my case since I have power and only slightly larger than stock tires. At least it won't cause (much) tire wear issues like toe or camber settings can if they are too far out. I looked at the shim measurements and my front diff pinion angle and decided to order a 6 degree.

 

… and increases the turning radius. Less caster = tighter turns.

 

… and increases the turning radius. Less caster = tighter turns.

What? Explain that one.

 

I don't know if caster is too forgiving. As an example, too little caster and your steering wheel will just stay where ever you leave it...no return to center function anymore. Its hard to imagine until you hit that point and then you experience it and in my case I hated it. With good caster you take a turn and the steering wheel starts coming back to center on its own after you exit the turn. With poor caster you take a turn and then have to start moving the steering back to center manually. To me it is really a really unsafe and forklift feel. I would do my best to keep alignment specs as close to stock as possible.