Agreed! A fix would be nice. But owning a tractor could get you sued. Going outside could get you sued. Being a good neighbor could get you sued. There's no reason to think that modifying your tractor makes you more likely to get sued. Let alone the dealership.
The very act of existing as a corporation with a lot of money is what makes you a lawsuit magnet. Nothing you can do will prevent that. Trying to prevent people from making modifications to their tractors they bought from you is just as likely to get you sued as not trying to stand in their way.
There are corporations that are well-known to use lawsuits as a way of silencing people. They have lots of money to keep lawyers on the payroll and bankrupt their opponent.