I would be surprised if a 16 will fit on a 16.5 rim, but I am sure it has been done with success being all over the place. I thought all 16.5 wheels were split rim requiring a tube? Maybe not.
I recently had a shake I could not figure out. I jacked the rear of my truck (03 Ram with a 22.5" conversion) and brought the tires up to speed. You could clearly see one tire was out of round. Went to the tire shop with other tires I had and they showed me it was not mounted straight on the wheel. It was offset a little on the bead causing the issue. They said with heavy OTR trucks it would pound it into place, but with mine it needed to be paid attention to. They got it on straight and all was good.
