XJ have an ongoing shimmy on highway and impending DW between 40-50 mph, DW when slowing down on highway exit ramp.
I finally took the time to inspect its steering components. Nearly all of them are bad!!! All 4 TREs (GM 1 ton), loose track bar heim at axle side, rust seized on frame side, steering box sector shaft (side to side with a clunk). Ball joints are still fine. Approximately 15,000 miles since the build, most are road miles.
I think some of it may have to do with steering stops on knuckles not perfectly matched with box? I welded a little on inner Cs to stop axle shaft yokes from touching each others.
Either way, I’ll tighten the steering box, replace all of TREs & heims.