disco 1 wheel wobble?

Just nipped out to the shop for some late night supplies and driving along it felt like my rear passenger wheel was lose every time i went over even a tiny bump it vibrated like mad... and under braking...

So stopped checked the wheel nuts... all tight.

Went up to my unit and jacked it up... no play in any of the wheels, looked under it...had a quick play with all the bushes... all looks fine...

What the hell could it be?

Bad damper?

Thats what ive just been thinking... and first thing im going to change in the morning if i can get two...