there not on the rim ewest lol. due to semi tires have so much steel belt from having to take a lot of road use, long as you don't trap air in the sides they sink on there own, they have been in the same spot he have thrown them in at for over 20 years. He didn't fill them with any thing the BG just found them and dished it out even deeper, I figured sand and gravel would make it more appealing to them.

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