Whirring noise on hard right/left turn / juddering grip?

Hi all

Any ideas what this might be?

Megane 300, making whirring / whining noise on full lock left or right, e.g. if turning out of a junction slow speed.

Also feels like it loses traction and tyres don't grip / slip. It judders as it does it, until I straighten up. Tyres in good condition.
Similar when parking and have it turning on a hard lock, feels like its skidding / like an understeer feeling.

Got it booked in for diagnostics but thought I'd check on here first if anyone has any ideas