Caster angle off on one side?

Chris

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After my suspension install the steering wheel returns to center just fine, and aside from my vibration (yet to be identified) the Jeep drives perfect.

I was measuring my caster angles today just to check, and the drivers side is 9 degrees, while the passenger side is 6 degrees. I measured them multiple times with my digital angle finder (from the bottom of the knuckle) just to be sure I wasn't misreading. Sure enough, it was the same readings each time.

Is this odd? Better yet, is this even possible?
 
There should only be about a .4 degree difference in caster angles between the sides, not 3 degrees. But it is difficult for me to get an accurate caster angle, I personally only trust what an alignment rack indicates where the caster angle is concerned. I'd take it to an alignment shop and get their opinion.

Here's an old thread on it... http://www.jeepforum.com/forum/f9/dana-30-pinion-caster-angle-delta-616920/. It's the same whether it's a Rubicon Dana 44 or TJ Dana 30.
 
I'm not even sure how it would be possible to be off by that much on one side. I mean the only way it's possible is if one of the control arms is adjusted way off on that side I assume.

I'm tempted to take it to an alignment shop, but I don't know of any that will touch adjustable control arms. Maybe I'll just have to call around and see if any of them will mess with lifted 4x4s.
 
You couldn't mis-adjust a control arm so it'd twist the axle and cause a caster angle difference between the sides. I'd just have an alignment shop verify the cross-caster angle between the sides. The only type of shop I would expect would be willing to adjust the control arms, if needed, plus do an alignment would be a 4x4 shop that also has an alignment rack. I doubt a straight alignment shop would be interested, except to just check/confirm the caster angle for you.
 
You couldn't mis-adjust a control arm so it'd twist the axle and cause a caster angle difference between the sides. I'd just have an alignment shop verify the cross-caster angle between the sides. The only type of shop I would expect would be willing to adjust the control arms, if needed, plus do an alignment would be a 4x4 shop that also has an alignment rack. I doubt a straight alignment shop would be interested, except to just check/confirm the caster angle for you.

That's what I thought, how in the hell could a control arm be adjusted that it would twist the axle... Very unlikely, if not impossible.

I'll see if I can find a 4x4 shop with an alignment rack. Of course I probably shouldn't even bother at the moment, I need to install this Savvy transfer case skid (whenever I hear back from Martin) so that I can get everything in order since the angles will change yet again with the skid plate.
 
That's what I thought, how in the hell could a control arm be adjusted that it would twist the axle... Very unlikely, if not impossible.

I'll see if I can find a 4x4 shop with an alignment rack. Of course I probably shouldn't even bother at the moment, I need to install this Savvy transfer case skid (whenever I hear back from Martin) so that I can get everything in order since the angles will change yet again with the skid plate.

I know this is from awhile ago but what was the reason? Im having the same issue.
 
I know this is from awhile ago but what was the reason? Im having the same issue.

Oh wow, this is from 2-years ago.

I honestly don't even remember other than that I took it to an alignment shop and they fixed it. I wish I remembered more, but this isn't fresh in my head at all.
 
Oh wow, this is from 2-years ago.

I honestly don't even remember other than that I took it to an alignment shop and they fixed it. I wish I remembered more, but this isn't fresh in my head at all.

Haha sorry about that

What im getting is I want to adjust as much as I can (Longer) on my lowers and (Shorter) with my up'ers with out messing up my driveline? IDK why but the Castor, pinion angle thing I cannot grasp it on what I need to do for my jeep.
 
Haha sorry about that

What im getting is I want to adjust as much as I can (Longer) on my lowers and (Shorter) with my up'ers with out messing up my driveline? IDK why but the Castor, pinion angle thing I cannot grasp it on what I need to do for my jeep.

Caster angle shouldn't be adjusted by you or me. That's something you need to take it to a shop to have done.

That being said, on my most recent TJ, I let the shop handle the caster angle, and the pinion angle was a byproduct of that.

The front pinion angle isn't important like the back pinion angle. In the front you need to worry about caster.
 
Does the measurement matter? When I set mine, I added caster until I was comfortable with the pinon angle. Then I double checked droop to make sure there was no bind. That's it.

Pinion takes priority over caster.
 
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Caster angle shouldn't be adjusted by you or me. That's something you need to take it to a shop to have done.

That being said, on my most recent TJ, I let the shop handle the caster angle, and the pinion angle was a byproduct of that.

The front pinion angle isn't important like the back pinion angle. In the front you need to worry about caster.

Okay I took it to a shop today and they called me back having no idea what to do.

They didnt like that I told them ill take it somewhere else.

I thought I could do it on my own. Im really trying to figure out why after I installed my JJ's on the axel that my steering is not straight any more.
 
Caster wouldn't have anything to do with your steering wheel being straight really, but it would have to do with your steering not returning to center for instance when you're driving your Jeep.

If you're having a problem with the steering wheel not being straight when the Jeep is parked, that has to do with your drag link needed to be adjusted.
 
Changing the pinion/caster could change the track bar and drag link enough that the steering wheel would need to be adjusted. It's all conected to the same axle.
 
Caster wouldn't have anything to do with your steering wheel being straight really, but it would have to do with your steering not returning to center for instance when you're driving your Jeep.

If you're having a problem with the steering wheel not being straight when the Jeep is parked, that has to do with your drag link needed to be adjusted.

When I'm parked it's all good. When I'm driving it turns slightly to the left to be straight. I would say a quarter turn.
 
When I'm parked it's all good. When I'm driving it turns slightly to the left to be straight. I would say a quarter turn.

When you turn, does the steering wheel want to return to center on its own?
 
I know this is from awhile ago but what was the reason? Im having the same issue.
You can't measure caster from the knuckle casting, they aren't always aligned square to the ball joints. That's why you have a shop do it, the alignment machine measures caster by watching the wheels move. Once you learn how your axle is aligned you can adjust from there but you need to have it on a rack at least once to get the baseline. In other words if the shop says your caster is 6 and you measure 3 on your left knuckle with an angle finder then you know you can get your caster by adding 3 to your left knuckle measurement. Hope that makes sense, the axle casting just isn't a calibrated surface.
 
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When you turn, does the steering wheel want to return to center on its own?

Yes it does. Not like a race car but it does. The reason I feel like I messed it up is when I changed the Jonny joints on the axel it made the wheel not straight on the road.
 
20190128_162839.jpg
 
The Johnny Joints themselves have nothing to do with it. It is possible however that you have one or more control arms fighting against the other one. Meaning one is extended far more than the others and is thus putting pressure on things.