caster/pinion angle, New driveshafts

07wranglerX

New member
I bought an 07 jk 2 door that the PO had installed a 4.5" lift and 35s. I found out that the stock driveshafts were never replaced. After doing a bunch of research. I have a pair of Adams driveshafts on order. After I got those ordered I started looking into adjustable control arms which lead into the pinion/caster issue. So I bought an angle finder to get an accurate reading. I found that I have 0 caster and 6 degrees of pinion. I measured from the pinion yoke and the two flat spots on the diff. The part that confuses me is that I don't have any of the issues that are normally associated with low caster angle. I don't have flighty steering, bump steer, or dw. The question is, since it seems to be driving fine should I just leave the angle alone when I install the new driveshaft?
 

wayoflife

Administrator
Staff member
Holy cow your Jeep is sky high!! If you're absolutely sure that you have 0° of caster and still have no handling issues at highway speeds, all I can say is that you are proof that ride quality and handling are completely subjective. If your Jeep were mine, I would lower it substantially and yeah, I would make sure that I had proper caster set but, that's just me.
 

07wranglerX

New member
Holy cow your Jeep is sky high!! If you're absolutely sure that you have 0° of caster and still have no handling issues at highway speeds, all I can say is that you are proof that ride quality and handling are completely subjective. If your Jeep were mine, I would lower it substantially and yeah, I would make sure that I had proper caster set but, that's just me.

Yeah I'm pretty sure about the angles. The front of the diff is vertical and the yoke angles up 6 degrees towards the tc. As far as handling, this is my dd and I can the it up to 80 on the interstate no problems. As far as the angle are you saying that using adjustable control arms to increase caster can only improve the ride?
 

wayoflife

Administrator
Staff member
If you your angle finder is giving you a reading of zero on the front of your diff, that does not mean you have zero caster. Try placing your angle finder on top of your ball joints and see what it says.
 

07wranglerX

New member
wayoflife. Also do you have recommendations on adjustable control arms? I'm just out if college so money is pretty tight after buying driveshafts. I'm looking for the best bang for your buck.

Yeah the jeep sits pretty high but I like it. I'm 6'8" tall so it's nice to not have to step down into a vehicle.
 

wayoflife

Administrator
Staff member
Yeah the jeep sits pretty high but I like it. I'm 6'8" tall so it's nice to not have to step down into a vehicle.

Well, to each their own for sure. I run 40" tires and do it with just 4" of lift. A lower center of gravity can be your friend on the trail.
 

wayoflife

Administrator
Staff member
Don't know how that is possible IF you really are getting a zero reading at the diff. As you can see in the pic below, when your angle finder shows 92° or 88° here...
attachment.php


You would be getting 4° here...
attachment.php


A zero reading at the front would give you 2° more giving you a total of 6° of caster.

Might want to double check that the ground you are on is in fact zero.
 

07wranglerX

New member
Might want to double check that the ground you are on is in fact zero.[/QUOTE]

I forgot that one little step and I think I mixed up my numbers to begin with...don't I feel dumb now... So after re measuring from the ball joint and accounting for ground slope. I'm right around 4 degrees caster and 2 degrees pinion. Which is where I should be which means this thread isn't needed. I'm assuming then that the PO did replace front control arms, he just did it with fixed arms instead of adjustable. I did see teraflex on the coils but didn't see any other brands visible on other components.
 

jims68

New member
Eddie is right on the money! Important thing is are you happy with the handling? I was basically in the same boat as you at 2.5 degrees and had quite a bit of feedback with off camber road surfaces. My wife was nervous with it so I turned the c's and am at 6 degrees now. There are so many things that could influence this like back spacing, tires, size of tires, drive shaft, lift, track bar orientation, drag link, toe all the way to manufactures and mixing of products. Sure sounds like your handling is OK for you so see if the new drive shafts are happy with your setup and don't vibrate I wouldn't touch it either!
Eddie are you planing on doing any changes to your tuning on your LS? I just went through and finally like what I have in mine but had some issues. Thing is very friendly like stock until you start getting into it! If you have any interest let me know and we can talk.
 

Seahawkfan

Hooked
I realize this is an old thread, but I have no clue as to what my front caster or pinion should read? I have 3.5 lift, To me it drives great. Nothing to compare it to. Have a vibration at 60 mph and only 60 mph not 59 or 61. Even with the new J.E. Reel front shaft. Attached a picture of the angle. Any help would be appreciated. 20181009_144111.jpg 20181009_144119.jpg 20181009_144102.jpg
 

WJCO

Meme King
I realize this is an old thread, but I have no clue as to what my front caster or pinion should read? I have 3.5 lift, To me it drives great. Nothing to compare it to. Have a vibration at 60 mph and only 60 mph not 59 or 61. Even with the new J.E. Reel front shaft. Attached a picture of the angle. Any help would be appreciated.

Usually if a vibration only occurs at a certain speed, it's related to tire balance.
 

Seahawkfan

Hooked
Usually if a vibration only occurs at a certain speed, it's related to tire balance.

That's what I was thinking. If I remember correctly I did drive It without the front shaft and it was still there. My real question is what do you think of the angle? Thanks
 

WJCO

Meme King
That's what I was thinking. If I remember correctly I did drive It without the front shaft and it was still there. My real question is what do you think of the angle? Thanks

If your ground is a perfect flat 0, then where you are measuring at on your pumpkin (from the passenger side view), you should be at 88 according to this thread: https://wayalife.com/showthread.php...nt-End-Alignment?p=42391&viewfull=1#post42391.

So it looks like you could add about a degree or slightly more to obtain optimum caster. However, as caster increases, front drive line angle is less ideal. So, if it is a driveline vibration that you have, it will probably get worse if you increase the caster. If you're happy with the way the Jeep's steering feels, I wouldn't mess with the caster personally.
 

Seahawkfan

Hooked
If your ground is a perfect flat 0, then where you are measuring at on your pumpkin (from the passenger side view), you should be at 88 according to this thread: https://wayalife.com/showthread.php...nt-End-Alignment?p=42391&viewfull=1#post42391.

So it looks like you could add about a degree or slightly more to obtain optimum caster. However, as caster increases, front drive line angle is less ideal. So, if it is a driveline vibration that you have, it will probably get worse if you increase the caster. If you're happy with the way the Jeep's steering feels, I wouldn't mess with the caster personally.

Thank you. Appreciate the help.
 
Top Bottom