+14° of Caster!?!?

Charlie Mike

Charlie Mike

New member
A few days ago I started to feel my jeep wander ever so slightly on the freeway. Didn't think too much of it till today when I noticed my front axle had way more positive caster than normal. Looks like +14° (according to my iPhone). Enough to notice by the naked eye. I'm going to adjust it back to normal sometime this week. But is this common? What causes this? I'm just surprised by how much it actually adjusted itself.

caster1.JPG

caster2.JPG

caster4.JPG

caster5.JPG
 
upper control arm or ball joints gotta be shot.
I'd put it in 4wd and leave it in gear... then rock the jeep to and fro while under it and see where the axle is moving. look close at the control arm mounts.
 
Elusive said:
upper control arm or ball joints gotta be shot.
I'd put it in 4wd and leave it in gear... then rock the jeep to and fro while under it and see where the axle is moving. look close at the control arm mounts.
Click to expand...

Oh, Woe is Me! :grayno: I'll give it a shot. Hope this is not the case. Thanks Elusive.
 
Please get back to us when you find the problem. It will be interesting to see what it is. I can't believe it's ball joints unless they are totally broken off. I would look at upper and lower control arms and mounts as above has mentioned.
 
14* at the ball joint? Was there a difference when measured from the differential housing?
 
MTG said:
14* at the ball joint? Was there a difference when measured from the differential housing?
Click to expand...
Hmmm??? Now it says 7° :idontknow:
caster6.JPG

OverlanderJK said:
You axle is off for sure but I would get something better then your iPhone to measure.
Click to expand...
Yup! Definitely going to go buy a real angle finder for sure.

Elusive said:
How are you measuring the caster?
Click to expand...
iPhone (Just for a rough idea). But I can see it's way off just by looking at it.
 
Charlie Mike said:
Hmmm??? Now it says 7° :idontknow:
View attachment 65615


Yup! Definitely going to go buy a real angle finder for sure.


iPhone (Just for a rough idea). But I can see it's way off just by looking at it.
Click to expand...

Yeah, at 14* of caster I would have expected that you would experience more than a slight wander. But hey, I'm no expert. I'd do as above and double check the measurement with an angle finder. :thumb:
 
Take a picture from the side so we can see pinion angle vs castor angle. It looks like a stock housing and if so there should only be 6-7 degrees of total separation between pinion angle and castor angle.

Is the pinion pointing down? Is the top of the ball joint point towards the rear of the Jeep?
 
I recently checked my alignment with the iPhone after zeroing it to the garage floor with a long level. One level app indicated I was at 10˚ castor and the app was unresponsive, particularly when the phone was vertical, as you normally hold it. It seemed to work fine when the phone was laying flat on the table. Another app that was advertised for measuring angles was very responsive in all positions and indicated 6˚castor. After testing the second app in some different scenarios it seemed very reliable and accurate. Before I figured out the software was the problem I was pretty concerned with possibly ripping apart my TF bushings.

It doesn't look like the phone is your problem though.
 
Last edited:
As someone above mentioned, there is about 6* difference from caster to pinion. So, your readings at least match. I sometimes find it can be hard to get a solid stance on top of the ball joint, but seeing as your readings match that isn't it. Was the vehicle level when you took these readings? That can throw you off, doesn't take much of slope in your driveway to be a few degrees. I would at least verify your iPhone reading against a quality angle finding device. But, with this much caster, if it was simply a caster setting, you won't have wander. It would be hard to steer from straight, and would want to return to straight rather aggresively.
 
AppBox is dead on. If you calibrate it first. If your driveway is inclined, it will include this to either increase or decrease your reading.

I've used AppBox for about 4 years I a regular (near daily) basis. It matches perfectly with my magnetic angle finder.


Sent from a a few tin cans and some string.
 
So..... did you check your upper control arm mounts and bushings? Forget the angle finder and numbers they are giving you, your axle LOOKS off and the most likely cause of that is a problem there. Let us know what you see.
 
So looks like the small nut & bolt that clamps down on the johnny joint securing the control arm length was loose on both of my lower control arms. Uppers looked good and tight. Passenger's side lower control arm was way extended, and the driver's side lower control arm was at it's shortest length. I dropped the passenger's side joint at the axle and tucked things back in to match the driver's side length for now. Getting that joint back into the bracket was a PITA last night! So instead of doing it myself, I'm just going to send my rig for an alignment. As well as schedule some general maintenance with Off Road Evolution.

Passenger's side lower control arm
caster arm1.JPG

Driver's side lower control arm
caster arm2.JPG

Passenger's side coilover and airbump
caster shock1.JPG

Driver's side coilover and airbump
caster shock2.JPG

Shaved the tip of the nylon contact pad
caster bump2.JPG

Also tweaked the sway bar link bracket
caster sway1.JPG

caster sway2.JPG
 
For the safety of the rest of us, check out your trackbar and tie rods as well.
Hell, do a complete suspension inspection. Check and make sure everything is torqued to spec. I do this after every time offroad.

Sent from my SCH-I545 using WAYALIFE mobile app
 
You must log in or register to reply here.
Top Bottom