My 2023 has filled rear tires as per dealer recommendation- I think LS or your dealer is giving you the run around- Ballast on a tractor with loader is industry standard as Guesseral has said above. BTW My tractor is in right now for service and one of my issues is the rear diff. doesn't seem to be working-- we'll see what my guys say. Good Luck
Can you PM me with info on what dealer has your tractor? My dealer said that LS told them my tractor is the first they've heard of a having a rear diff problem. If I had the info, I can give it to my dealer and tell them mine is certainly not the only one with the problem.