Caster question...

Just recently installed the rough country control arm drop brackets. Currently, the passenger tierod end is scraping the bottom of my jks discos. (common problem.) I have fixed uppers and lowers...adjustables would make things easier, but I don't have them. Question....if I add shims to my lower control arm and push it forward...therefore rotating the axle backwards (up and back)...does this increase my caster or decrease my caster? Just took into to get an alignment and requested that they shim it...of course they didn't bother listening to me and just adjusted the toe and said things were great (2.5 degree caster isn't great). If I rotate the axle backwards a bit, I think that will give me more clearence on the tierod end/sway bracket issue...but will it give me better caster or worse? Thanks!

Yes, rotating the top of the axle housing rearwards (pinion rotating down) will increase the castor. 3-5* has always worked OK for me, stock spec is 5-7*.

Shimming will improve your caster. It will also most likely worsen your front driveshaft/pinion angle. I just tried shimming my non-adjustable LCA's to fix the tie rod / sway bar link interference problem and found that even adding the max amount of shims (~1/4"), my tie rod still hit the sway bar link.

Thanks guys...I finally found a diagram that shows that it will indeed increase "positive caster"...just like you mentioned. The tierod barely touches the bottom of sway bar bracket now...I am hoping that the small movement in the caster will keep it from touching at all. I am now nervous about the contact of these components when flexing though. I am not too worried about the pinion angle...I have the HP and have never experienced any vibes...hopefully this small change will not bring on the vibes! If I have to, I guess I will need to purchase the exteded sway bar brackets from polyperformance. Everything else looks great with this setup. Tires are dead center of the wheel well...coils are straight and not bowing at all. rides great...just want a bit more caster to alleviate the small "wandering" feel. (and of course alleviate the binding on the tierod)

Let us know how it goes...

Well, I don't have any threads left on the alignment shoe bolts to add any more shims to the LCA pocket! It looks as if the LCA is as far forward as it is going to get. I guess my only option to rotate my axle is to find an adj UCA that will adjust shorter than stock? My lowers seem to put the axle in a perfect spot. Coil is straight and wheel is centered in the wheel well...no reason to mess with the lowers then, ehh? Is this my only option in my situation. (I know I can get all adjustables but that just isn't going to happen...don't have the funds...I would just go long arm at that point)

Relocate/extend your axle side sway bar brackets or click over to PolyPerformance.com and buy their sway bar relocation brackets.

Peregrine said:

Well, I don't have any threads left on the alignment shoe bolts to add any more shims to the LCA pocket! It looks as if the LCA is as far forward as it is going to get.

Click to expand...

Pull the alignment shoes out. Cut and drill the old bolts off and use some longer ones.

If your alignment shoes have square holes (some do), you can use carriage bolts. If they have round holes, you can either weld the new bolts in place, or just use a wrench to tighten them up.

I used like 3.5 to 4 inch bolts and then trimmed them down once it was all put together. My LCA's are as far forward as the oval hole will allow. Rides great now.