New TJ owner. Need help sorting alignment...

[rraulston]

So I picked up a new to me 2005 Rubicon. It was barely drivable. Severe bump steer/wobble/drift, you name it. After doing a lot of research on here, and physically checking the Jeep, all 4 shocks were bad. Zero dampening. Replaced with Bilstein 5100. Drop pitman arm was replaced with a factory one. All steering linkages was replaced with the Currie set up. I believe it has a 4" Rubicon express lift. All 8 control arms were removed and all bushings replaced. All Johnny joints were rebuilt. The rear axel was 3" left. I re-centered the axel. All 4 tires have 500 miles on them. This is an AZ rust free jeep in great condition. The previous owner just thought that's how Jeeps drove I guess. All new sway bar bushings. Both front and rear track bars are adjustable, BUT they are attached to the factory locations. After doing all of this and getting an alignment. I am 80% better!! It drives good. But it still has a slight wander. After reviewing the alignment sheet, what are your thoughts to get it as good as new again?? Or am I there considering the lift?? My thoughts were getting both front and rear Currie track bars, lower adjustable control arms in the rear to adjust the thrust angle (top arms are adjustable and all lowers are fixed). The tech couldn't get the caster at 5' as the cam bolts only gave him 1' and he wouldn't take off the arms and adjust them. I thinks that it...…

If I wanted more caster, would I extend the top front arms or retract them?? Thanks for your time...

 

[Boinked]

You might want to consider taking it to 4 wheel parts down in Tucson and have the adjust the control arms. They will realign it.

Firestone is great after they are set. But they wont adjust them unless they are double adjustable.

As far as wondering steering. I have the same problem in my 97. I have narrowed it down to the weak "return to center" i believe it is caused by my lift and 33x12.5 tires. Mine is not horrible and thinking that it might improve when i redo my lift.

 

[Jerry Bransford]

In the interest of keeping the front axle positioned where it is and not moving forward or backward, you need to equally adjust both the upper and lower control arms Shorten the upper arms and lengthen the lower arms an equal number of turns to increase your caster angle while keeping the axle positioned where it is.

However, how much caster angle you can obtain without getting vibrations requires you not increase it to the point it will cause an excessive angle between the pinion shaft and driveshaft where the u-joint is. The pinion to driveshaft angle can only go so far before it will cause the u-joint to start vibrating. The rule-of thumb is to increase the caster angle until you get a vibration then back it off a tad to the point the vibration is completely gone. The pinion angle takes precedence over the caster angle. How much caster angle you need for steady steering also depends on your tire size, the bigger the tire the less caster angle that is required. So for a 35" tire, you don't need the full 7 degrees. As close to 6 degrees as you can get would be a good goal for your tire size which looks to be about 33".

 

[rraulston]

You might want to consider taking it to 4 wheel parts down in Tucson and have the adjust the control arms. They will realign it.

Firestone is great after they are set. But they wont adjust them unless they are double adjustable.

As far as wondering steering. I have the same problem in my 97. I have narrowed it down to the weak "return to center" i believe it is caused by my lift and 33x12.5 tires. Mine is not horrible and thinking that it might improve when i redo my lift.

Interesting comment. I have no idea if the arms are properly adjusted. Based on the shoddiness of the install and what I believe to be binding of the axel, I might start there. I had to put a chain on my tractor and pull on the axel to position the arm in order to insert the bolts. Now I did have the spring in so maybe the load was from that...dunno… I just reviewed a video and might remove the springs and jack the axel and align the bompstops. Or take it to 4wheel parts. Its hard to know where you are going if you don't know where you are at!!

 

[rraulston]

In the interest of keeping the front axle positioned where it is and not moving forward or backward, you need to equally adjust both the upper and lower control arms Shorten the upper arms and lengthen the lower arms an equal number of turns to increase your caster angle while keeping the axle positioned where it is.

However, how much caster angle you can obtain without getting vibrations requires you not increase it to the point it will cause an excessive angle between the pinion shaft and driveshaft where the u-joint is. The pinion to driveshaft angle can only go so far before it will cause the u-joint to start vibrating. The rule-of thumb is to increase the caster angle until you get a vibration then back it off a tad to the point the vibration is completely gone. The pinion angle takes precedence over the caster angle. How much caster angle you need for steady steering also depends on your tire size, the bigger the tire the less caster angle that is required. So for a 35" tire, you don't need the full 7 degrees. As close to 6 degrees as you can get would be a good goal for your tire size which looks to be about 33".

View attachment 59697 View attachment 59698

I only have adjustable upper arms. The lower arms are fixed. So if I just shorten the upper, that will give me more f the desired caster?? Or do I need to buy adjustable lowers?? Thanks

 

[Thunderhead]

Sweet looking Jeep! What kind of roof rack is that ?