so I had a flexing, groaning sound from my front DS wheel area,

thinking expensive nasty unit bearing/ball joint/uni job

lets check first, and indeed the front knuckle is grooved, I welded and ground the other side before

this can turn nasty if let go, cook your caliper, pads, disc, leave you stranded

weld & ground..all fixed..no flexing sound

the other side was different, no noise, but the caliper wedged in, heating brakes, luckily was local

this will get you eventually all XJ owners, worth checking, very quick thing to do