Caster adjustment advice?

Technically aren't the tubes just pressed into the center housing? Folks have spun axles tubes.

-Mac

Technically, yes, but there is a bit more to it than just pressed in. There is a finely calculated amount of press fit interference and then the casting is heated to expand the sides. When it is pressed in, there is also some very accurate alignment going on since both sides are welded up with the C and mounts before they go in. After they are in, then there are several plug welds to act as mechanical fasteners since the welds don't bond that well to the casting.
 
Your first method of measuring should be ignored by everyone. It is a rough forging, not nearly accurate enough for anything worthwhile. The best spot to measure actual caster from is just inboard of the lower ball joint on the machined surface.
I believe that. I did not see a machined surface to put the angle finder on. I am guessing it would be easier to see if I pulled the tire? Any chance you have a pic of where that surface is exactly?
 
I believe that. I did not see a machined surface to put the angle finder on. I am guessing it would be easier to see if I pulled the tire? Any chance you have a pic of where that surface is exactly?

Impossible to miss. It is the only machined flat spot on the inner C just inboard of the lower ball joint. You need a clean spacer around 2" x 1/8" x 6" long to fit in there and give you a parallel surface to put the angle finder on. The reason you can't use the top of the upper ball joint is it leans. That means the angle finder has to be perfectly parallel to the centerline of the vehicle to read the correct angle and that is near impossible to do. Easy to check. Set the angle finder on the top of it, read the angle and then rotate it side to side slightly and watch the angle change.
 
Ok, I was looking for a big easy to get to flat spot like on the front of the diff. You say impossible to miss, but I have missed more obvious things when I didn't really understand what I was looking for and hoping it would jump out and bite me. Everyone's advice, guidance and patience with me is much appreciated.
 
My jeep is wheels off on the lift at the moment so it was easy to get some pics. I think this is the spot @mrblaine is referring to:
IMG_6084.jpeg


IMG_6085.jpeg

In the 2nd pic, I don’t have the straight edge up against the flat machined surface towards vehicle midline, but I think that’s also important for obtaining a reproducible measurement.
 
My jeep is wheels off on the lift at the moment so it was easy to get some pics. I think this is the spot @mrblaine is referring to:
View attachment 499925

View attachment 499926
In the 2nd pic, I don’t have the straight edge up against the flat machined surface towards vehicle midline, but I think that’s also important for obtaining a reproducible measurement.

Perfect, thank you. One could check that, then the flat spot on the front of the diff castings, calculate the difference and then move to the easier to use flat spot.
 
Check your pinion angle from the rear of the axle. With the angle gauge rotated correctly it will directly show the pinion angle.

View attachment 498746

View attachment 498747

Jerry, so taking consideration of the slope of the floor, If i put my angle finder on the machined spots on the differential i can find out what the pinion angle is ? than take 12 and deduct the pinion angle and end up finding out my caster ? the reason I'm asking is when i removed the 3" of so lift springs and returned to stock springs, i never replaced the lower control arms. The control arms don't look stock and wondering if they are to long.
 
The stock lower control arm holes are 15-13/16" center-to-center. You should be able to measure yours on the Jeep, centering on the bolts.
 
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