Glenn,
It could be the same problem, tyre age, as everyone rightly says over five years old irrespective of mileage they really need changing. Don't forget you're only in contact with the road on four palm prints, yep that's the contact area, and they need to be good ones in my book.
I favour toyo proxes for my plus 8 but not sure if they do them to suit a 4/4
Good luck, safe driving
