cheers saint. what about the test of reversing with steering on full lock and listening for chirping or jerkyness - is that also for VCU?

Yep, it works going forwards too....the only problem is if it has seized and you do that test, you could be making it worse.....

If you do try it, best to do it on a lose surface to allow for tyre slip so you don't damage anything.....

VCU lockup when driven slowly on gravel will make the tyres skip and slid on full lock....