So we installed new lift on Jeep. 4.5 RC Xseries with Adj upper and lower control arms. Bought some new steal wheels and some used tires. About 1/2 tread left. Yes I have death wobble very bad. I read all this talk about caster. I understand all that. But heres the thing. I went by the specs that RC sent with their UCA and LCAs concerning lengths. Also installed new track bar and went with specs from RC on that length as well. Now my questionis this. Before I work on caster....should I check toe or should I check axle placement(side to side)? I guess Im asking do you do side to side before you check wheelbase and caster. I firmly believe I can do this but dont wanna be counter productive.

 

Yes, your toe will be off a lot. It would be the last thing to do because everything else affects it.

 

Center Axles ,Set Caster then Toe. Drive it ,,the setting you were given are starting points every vechicles gonna be a little different .Bookmark this for reference ....http://go.jeep-xj.info/HowtoAlignment.htm

 

Are the lower control arms shimmed at all from the factory?

 

They're all set up from the factory with the caster shoes. Some have shims and some don't but it will have the shoes regardless since the frame bracket is slotted.

 

Heres my scenario a lil better. I bought Jeep and it had what Im thinking was a 2" lift. Factory upper and lower control arms. I installed 4.5" lift. I actually got 3.25" of lift. Which tells me old lift had sagged. I put adj control arms to RC specs. I didnt find shims until after install was complete. It has 1/4 worth of shims. So If my LCAs are supposed to be 16.5+- and then add .25 to that. Am I at 16.75 or is .25 worth of shims from factory considered "zero"?

 

As it stand right now. Ill be driving it at 20mph to the alignment shop. Its that bad

 

The shims were most likely there because of production variances on the pocket and where it is. Can treat it as a stock set up and put the arms where the instructions say as a baseline. There is a tradeoff between caster and pinion angle when you lift it.

 

Don't need to add or subtract shims with adjustable arms .You adjust the arms ....

 

Caster settings on chart at bottom around 5.5 should do ya at 4.5 lift....http://go.jeep-xj.info/HowtoAlignment.htm

 

As you van clearly see the top of the tire is leaning in. I believe I have more than just an alignment issue. With 240k miles Im sure balljoints as well as steering components need replaced.

 

Whats your toe set at should be 1/16 closer in front than rear.

 

Idk to be totally honest. We did some preliminary measurments but its me weekend to work and time has been very limited. I will say now that I have a better understanding about caster. My lower ball joint is further forward than my upper. Meaning I have positive caster angle. And it look like way too much.

 

There is a significant difference of the vertical plane between the upper and lower ball joint. This is normal and needs to be checked with an angle finder.

 

Boy talk about feeling stupid. The first thing he noticed is that my track bar was loose. Really loose. I just installed it and its brand new. Go figure. All I can think is when I installed it I got tie rod end off center and when I first aoolied brakes after installation is when death wobble occurred. He tightened it up good and death wobble is gone. Although he did say my steering components and ball joints did show signs of wear. And get this. My brand new Rough Country track bar. He showed me how much slack it had in it and Its brand new. That blows. I will be taking the end off of that thing and replacing it with a good joint. Now the alignment. He said I had 8 degrees of positive caster. He said he wanted to see 4 degrees. So he said for me to install all new parts and come back, He def did a lot of good. Thanks guys for the help. Im learning a bunch about XJs.