I can't count the number of times I've seen a forklift fork with a hole burned/bored out of it. I'm guessing, but most the time I'm betting it's just the right size for a tow ball. Not a good idea, OSHA frowns upon the end user modifying the fork. Hit a stress crack and you likely will be buying a new pair of forks. The better approach is to use an engineered apparatus that slides onto the forks like our Forklift Trailer Spotter or Medium Duty Trailer Mover .