Offset Camber & Caster

Never heard of such an animal. Can't just use shims to rotate the entire axle?

 

yes, camber/ caster shims for the upper ball joint studs. You'll need the spanner socket to install them. Torque to 50 ft. lbs., then rotate clockwise until desired camber/ caster is achieved, then install and tighten upper nut.....
IMO, camber need not be adjusted for road crown; make it the same on both sides. Caster, however, should be 1/2-1 degree higher on the right side to compensate, if road crown causes a drift to the right.... Just my opinion...

 

So the shims go between the knuckle body and the upper kingpin bearing?

 

Sorry. I assumed he had an open knuckle/ ball joint front axle....

 

D'Oh..you're right. I missed which Jeep this was for.

 

This is probably what you are looking for:

Offset upper ball joint set rings.Used to help add positive caster.
Standard and offset rings shown in the pic.
Here's a write up and a source:
http://www.offroaders.com/info/tech-corner/project-cj7/project-cj7-castor.htm
HTH

 

Sounds like the shim on the spindle that you speak of is for camber (which is pre-set at the factory and not adjustable without these aftermarket shims). Normally camber does not need to be changed. I have not run into anyone with a CJ needing to change camber.

The problem with tracking/wandering/return-to-center is usually from not enough positive caster. Things like extended shackles and lift kits change the caster angle and steps are required to bring it back into specification. Shims(wedges between the spring pack and the perch on the axle tube) may be used to recover big loss of caster (so is cutting the knuckles off of the tube, rotating and rewelding). The offset set rings I referenced above can help to recover a few degrees of positive caster.

Before you throw a bunch of money at shims and such... have you had the front end aligned? Post your results here for caster and camber. Also what symptoms are you experiencing that lead you to believe your C/C needs adjusted?
C/C may not be the only variable that gives certain symptoms. Worn steering components can act much like not enough caster angle.

Regarding the '78 CJ5 and '79 CJ7 front axle, they should be the same.

I see you have 4" lifts on the 78 and 79 rigs. Any longer-than-stock shackles on there too?
I suspect you may have caster angle issues, but can't say for sure without the alignment report and a description of symptoms.
By way of comparison, when I installed the '74 D30 front axle in my '71, it was very difficult to keep it between the lines at 30 mph, uncontrollable at higher speeds. I took it for alignment. Caster was 1.0 on one side and 0.9 on the other. I obtained some 5-degree wedges to put my caster back to the 5 to 7 degree spec, and driveability was back to normal.

HTH

 

According to those numbers, it should be pretty hard to drive.


Looks like your caster spec is 2-4 degrees positive (positive is tilted back from vertical), and you're at less than one degree.
Are the shims at NAPA the kind that go onto the stud of the upper ball joint, like the ones I have pictured above? If they are, and that gives you 1.5 more positive caster, then you'll be just a tad over minimum. I'd shoot for the high side by ordering 3 to 3.5 degree steel wedges and putting them between the spring and the perch, fat end forward.
Shims available here, among other places:
http://www.4crawler.com/4x4/ForSale/Shims.shtml

Looks like your camber is pretty well out of spec too. I guess shims are available for that too, but I have no experience with them.

 

The lift changes the caster angle. So do longer shackles. The shims, or wedges, would be used instead of the ball joint setrings from NAPA. You may have gotten some wuith the lift kit... but only use steel, especially up front. If aluminum or other soft metal ones came with the lift, use them for doorstops.

HTH Barry and good luck! I'm offline for the next week or so...
There's plenty of knowledgeable guys here who will pitch in if you need more info.