because the ATV is getting old.
Option #1 - pickup truck.
Pros: doesn't flip nearly as easily, you're safe from damage when inside (though the truck itself will take damage if an animal i.e. buffalo attacks it)
Cons: does not function well off-road, spooks all animals within render range
Option #2 - horse
Pros: handles off-road terrain better than the ATV, quieter and doesn't spook animals as much (within 200 meters maybe?)
Cons: slower than the other options, will be spooked by predators and run roughly 100 meters away (if you aren't on it)