Hi. Does a 2010 XKR have a power steering belt, or just a pump? Really loud grinding sound when cold. Thanks.

 

It's driven by the accessory belt.

 

I experienced the same thing recently. My XKR was a Florida car but after the temperature in Eastern North Carolina dipped into the teens my car was making a whining noise. Sounded like the SC was whining. Became more pronounced when turning the steering wheel. Power steering fluid reservoir wasn't low but fluid had little air bubbles in it like it was boiling.

https://itstillruns.com/do-power-ste...d-7715778.html

The fluid was leaking from one end of the steering rack. Dripping out of boot. I added some power steering stop leak and have my fingers crossed because it seems to have stopped leaking. Apparently the rack had never experienced temperatures that low and the seal was leaking.

Wishing you luck with yours.

 

hmmm. And yet I’ve driven mine in -40 without issue.