Front end alignment question?

How much caster is too much? After adjusting my LCA's to a chart that I aquired I now have 9.25* caster and a bad shimmy at 55mph. I know my toe- in is off but I want to get the caster set right first. I have 3.75" lift in the front and my LCA's are set at 16 1/8", the UCA's are stock. I adjusted the lowers to get my axle centered in the fender openings and they are but I do not like this miserable shimmy and I can't afford adj UCA's right now.

Everything in the front end is new, ball joints, TRE's, and unit bearings. I'm running 31's that are airsoft balanced and did not shake before the adjustment. I'm also running 1" spacers.

Need suggestions?

All of my other stock XJs run 8* caster, is 9.25* too much?

My FSM specifies that acceptable caster is from 5* to 9*, and that driveshaft angle overrides caster. After my lift and a prof. alignment, my caster was 6.8* and I still had DW at speed. We turned my LCAs in two turns and the DW vanished (approx. 1*, we figure, so I should be right around 5.8*).

PS So yes, 9.25* is outside of factory specifications (and is about where mine was prior to the professional alignment (we had done the "driveway" alignment) and I had DW even at low speeds).

8* is the max castor. Get yourself an alignment with 0* toe and between 6* and 8* of castor and you should be good. Castor really only affects steering return but too much might contribute to that shimmy your experiencing. Good luck. -Rich

Thanks, I'm going to adjust it back to around 7* and get the toe correct. I've always been able to set the alignment on a XJ in my garage with a tape measure and a magnetic angle finder with good luck and no bad tire wear, but I may have to spend some money and get it set dead on this time.

Hi,

How do you measure caster ?

I will have to deal with it soon, so I am just picking up info.

Thank you,
Andrey