check your CV boots if it is a front wheel drive, or just your bearings in general. Since we don't know the kind of car, it's hard to diagnose.
It could be your ball joints, that's what it was on my truck. Take it to a shop and get it checked out. Get it checked out very soon, & ball joints are expensive.
It probably needs steering fluid.
Check the steering fluid reservoir - it will probably need topping up - MAKE SURE YOU USE THE CORRECT TYPE
could be your wheel bearings
you might want to check your left side wheel bearings
maybe the flap obove the left weel has com loose something youv left in te boot and forgotten about
Bad wheel bearings usually cause a grinding noise, and are known to only cause it when turning.
Front drive axle joints bad
Are you sure the noise isn't in the front. Sounds like a right front wheel bearing,which is a common problem on these vans.
Might be worn drive shafts or loose wheel nut
Sounds like you have a bad left inner wheel bearing.
If a car makes noise when turning the tie rod can be worn. Tie rods allow a vehicle to turn, when they fail the steering wheel will knock and rattle making all kinds of noises.
If you lowered the car or had suspension/strut work done you can be rubbing The body in the boot?